Long-term measuring device for radial growth of trees

Abstract

The utility model relates to a kind of forest tree radial growth long-term measuring device, including the measuring scale main body and vice scale part of overall long strip, vice scale part is set at the first end portion of measuring scale main body, first perforation and second perforation are opened in vice scale part, the width direction of measuring scale main body Two sides are all provided with pawl assembly, each pawl assembly includes the multiple pawls sequentially spaced apart along the length direction of the measuring scale main body, each pawl is extended outward, and it is inclined to the side where the first end portion of the measuring scale main body, after the second end portion of measuring scale main body sequentially passes the first perforation and second perforation of the vice scale part, corresponding pawl can be limited at the edge of second perforation, with the increase of the tree breast height diameter to be measured, corresponding pawl on measuring scale main body can be reversely tilted by the edge of second perforation and pressed to make the diameter of measuring ring corresponding increase. The measuring device has the advantages of convenient, accurate, long-term stable and widely applicable.

Description

Technical Field

[0001] This utility model relates to the technical field of tree growth measurement devices, and in particular to a long-term measurement device for radial growth of forest trees. Background Technology

[0002] Diameter at breast height (DBH) is an indispensable basic indicator in tree growth research, making it crucial to employ a measurement tool capable of accurate measurement. Currently, two main types of tools are used to measure DBH: one is immediate measurement equipment, typically using tools such as DBH measuring tapes, circumference measuring tapes, measuring straps with locking switches, or vernier calipers. This method requires one person to operate the measurement while another records the data, measuring one tree before removing the equipment to measure the next. However, this method is not only time-consuming and labor-intensive, but also inefficient. Repeated measurements may introduce significant errors due to differences in measurement location, DBH tape tilt angle, and reading methods. It is also prone to oversights such as misinterpretation, mishearing, or misrecording, thus affecting the accuracy and scientific validity of the measurement data. The other type of long-term measurement equipment is the growth ring, typically used in large-scale ecological plots for long-term dynamic monitoring of trees. Currently, spring-structured growth rings are widely used, as disclosed in Chinese utility model patent application CN202121146995.4. However, this type of growth ring still has some shortcomings in actual use: when using it, the measuring ring needs to be wrapped around the tree first. If the measuring tape is too long, it needs to be wrapped several times. The excess tape is wrapped inside, and spring hanging holes are made with hole punchers. After adjusting the length and hole position, the spring is hung. This process is relatively cumbersome to install, and the extra measuring tape inside will also affect the measurement accuracy.

[0003] Therefore, existing long-term measurement devices for radial growth of trees still need further improvement. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a long-term measuring device for the radial growth of trees that is easy to install and accurate in measuring the current state of the technology.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problem is as follows: a long-term measuring device for radial growth of trees, comprising a main body of a measuring ruler that is generally elongated and a secondary ruler. The main body of the measuring ruler has a first end and a second end opposite to each other in the length direction. The secondary ruler is disposed at the first end of the main body of the measuring ruler. The front of the secondary ruler has a secondary ruler scale marking, and the front of the main body of the measuring ruler has a main ruler scale marking. The secondary ruler has a first perforation and a second perforation arranged sequentially at intervals along its length direction. Both sides of the measuring ruler main body in the width direction have pawl assemblies. Each pawl assembly includes a pawl along the width direction of the main body of the measuring ruler. The measuring ruler body has multiple pawls spaced at intervals along its length. Each pawl extends outward and tilts towards the side where the first end of the measuring ruler body is located. After the second end of the measuring ruler body passes through the first and second perforations of the auxiliary ruler part, the corresponding pawl can be limited at the edge of the second perforation, so that the measuring ruler body and the auxiliary ruler part together form a measuring ring with an adjustable diameter for being fitted around the tree to be measured. As the diameter at breast height of the tree to be measured increases, the corresponding pawl on the measuring ruler body can be pressed against the edge of the second perforation and tilted in the opposite direction, thereby increasing the diameter of the measuring ring accordingly.

[0006] The aforementioned "pawl assembly" refers to a structural set that achieves a one-way locking function. In this application, it specifically refers to a structure formed by multiple pawls arranged in a certain pattern on both sides of the measuring ruler body. Its working principle is similar to a ratchet and pawl mechanism, allowing free movement in one direction (the end of the ruler extends, making the ring larger), while being locked in the opposite direction (the ring shrinks).

[0007] The aforementioned "reverse tilting" can be understood as the strength design of the connection structure between the pawl root and the measuring scale body, which can both ensure that "the pawl and the edge of the second perforation remain in a relatively stable limiting state" and (when the tightening force is large) cause the edge of the second perforation to break and cause reverse tilting, thereby allowing the measuring ring to loosen and expand.

[0008] Considering the potential for skewing and jamming due to uneven force when the measuring ruler body passes through the corresponding perforation, and to ensure smooth and stable expansion of the device as the tree grows radially, as an improvement, the pawl assemblies on both sides of the measuring ruler body in the width direction are arranged symmetrically.

[0009] The symmetrical design of the pawl assembly ensures that the measuring ruler body is subjected to balanced forces, guaranteeing that the measuring ring remains concentric with the trunk cross-section during the extension process. This improves the stability and accuracy of the measurement, while also making the extension and retraction movements smoother and reducing malfunctions.

[0010] To ensure the pawl reliably engages with the edge of the perforation for one-way locking (preventing ring shrinkage), and to allow the pawl tip to be compressed and smoothly slide into the next locking position under sufficiently large counterforce (like tree growth), the distance between the base positions of the two symmetrically arranged pawls on the measuring scale body is less than the width of the second perforation, while the distance between the ends of the two symmetrically arranged pawls on the measuring scale body is greater than the width of the second perforation. This structural design achieves reliable one-way locking and controllable, tiered expansion capabilities.

[0011] To ensure the pawls on the measuring scale body can smoothly pass through the first perforation for initial installation, and to prevent jamming or damage at the first perforation, the width of the first perforation is greater than the distance between the ends of the two symmetrically arranged pawls on the measuring scale body. The larger size of the first perforation, acting as a guide hole, ensures unobstructed passage of the pawls during installation, making the device installation convenient and quick, while protecting the integrity of the pawl structure. The relatively large width of the first perforation prevents its periphery from obstructing or limiting the corresponding pawls, thus reducing resistance when the measuring ring is tightened and preventing unnecessary damage or deformation during tightening.

[0012] Considering that an excessively large angle of inclination of the pawl may lead to insecure locking and easy loosening, while an excessively small angle requires significant force from tree growth to propel the extension, reducing sensitivity and potentially damaging the pawl or the tree, the angle formed between the extension direction of the pawl and the length direction of the measuring ruler body is denoted as A, where the value of A ranges from 40° to 50°. This pawl angle range ensures optimal mechanical performance, providing sufficient locking force to maintain the stability of the ring while also allowing for sensitive and reliable tipping and extension even under the slight growth force of the tree. A is preferably 45°.

[0013] Considering that an excessively long pawl is prone to accidental contact leading to malfunction or damage, while an excessively short pawl may result in insufficient contact and engagement depth with the perforation edge, affecting locking reliability, the pawl length needs to be reasonably limited. As an improvement, the pawl length is denoted as L, and the range of L is: 0.3cm ≤ L ≤ 0.8cm, with a preferred value of L = 0.5cm. This pawl length range ensures sufficient structural strength and effective contact length with the perforation edge, guaranteeing locking reliability and the device's service life.

[0014] Considering that excessively large values ​​of h and m would reduce measurement accuracy (due to excessively large diameter changes represented by increasing the size of one pawl), while excessively small values ​​would affect the strength of the pawl root and increase manufacturing difficulty, it is necessary to optimize the distribution density and structural strength of the pawls. The dimension of the pawl root along the length of the measuring ruler body is denoted as h, and the distance between the roots of two adjacent pawls along the length of the measuring ruler body is denoted as m. The ranges of h and m are as follows:

[0015] 0.05cm≤h≤0.25cm;

[0016] 0.05cm≤m≤0.25cm.

[0017] The preferred values ​​for h and m are: h = 0.1 cm; m = 0.1 cm.

[0018] The aforementioned size range, while ensuring the mechanical strength of a single pawl, achieves high measurement accuracy (which can be understood as resolution), enabling the device to capture millimeter-level radial growth of trees.

[0019] To meet the reading habits and data processing needs of different users (diameter and circumference are commonly used data in forestry research) and avoid the need for secondary conversions, the main scale markings on the measuring ruler have two rows: one for diameter and the other for circumference. The circumference markings correspond to and match the diameter markings. This structural design provides a direct, dual data reading method, greatly facilitating users, improving data intuitiveness and efficiency, and reducing calculation errors.

[0020] To ensure the measuring device is securely fixed to the tree trunk and prevent it from falling off or shifting due to wind, rain, or animal contact, thus guaranteeing continuous long-term measurements, the back of the measuring ruler body is provided with an adhesive layer for attaching the device to the tree being measured. This adhesive layer provides a simple, reliable, and non-destructive method for installing and fixing the measuring device, ensuring its positional stability during long-term monitoring and thus guaranteeing the accuracy and comparability of the data.

[0021] The aforementioned "adhesive layer" refers to a material layer coated or pasted on the back of the device for bonding and fixing objects. Specifically, it can be high-strength double-sided tape, pressure-sensitive adhesive, self-adhesive, etc. Preferably, TPR or natural rubber-based adhesive is used. The adhesive layer can increase the stability of the measuring ring fixed to the periphery of the tree being measured.

[0022] As an improvement, the end of each pawl is constructed with an outwardly convex arc shape. The end of the pawl (i.e., the pawl tip) is designed with a rounded arc shape, with an arc diameter R = 0.1 cm (to avoid sharp edges), which can eliminate the risk of thorns from the edge of the caliper pricking the hand.

[0023] Compared with existing technologies, the advantages of this invention are as follows: The main body of the measuring scale of the measuring device passes directly through the double-perforated structure (i.e., the first and second perforations) of the auxiliary scale, and is automatically limited by the pawl assembly. This eliminates the need for wrapping excess tape, drilling, or using springs for attachment, allowing for quick installation by a single person and significantly improving operational efficiency. During tree growth, the pawl assembly can be reversed and tilted, causing the measuring ring to automatically expand its diameter and continuously conform to the tree's diameter at breast height (DBH), reducing measurement errors caused by displacement or loosening and ensuring the scientific validity and accuracy of long-term monitoring data. The pawl is angled towards the second end, facilitating smooth passage when inserting the scale and effectively locking it during pullback, forming a stable and adjustable measuring ring to adapt to the growth monitoring needs of trees with different DBHs, significantly improving practicality. The overall thickness of the measuring device of this invention can be thinner, allowing for better conformation to the outer perimeter of the tree being measured. Unlike some existing technologies where redundant designs or components result in an overall thicker measuring device, which can significantly affect the accuracy of measurement results. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural diagram of the forest radial growth long-term measurement device according to an embodiment of the present invention after it has been unfolded.

[0025] Figure 2 This is a front view of the forest radial growth long-term measuring device according to an embodiment of the present invention after it has been unfolded.

[0026] Figure 3 This is a three-dimensional structural diagram of the long-term radial growth measurement device for trees in use according to an embodiment of this utility model. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] In the specification and claims of this utility model, terms indicating direction, such as "front," "rear," "upper," "lower," "left," "right," "side," "top," and "bottom," are used to describe various exemplary structural parts and elements of this utility model. However, the use of these terms is merely for the purpose of explanation and is based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this utility model can be arranged in different orientations, these terms indicating direction are for illustrative purposes only and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

[0029] Figures 1-3This illustration shows a preferred embodiment of the long-term radial growth measurement device for trees according to the present invention. The device is an overall elongated strip structure made of flexible ASA (acrylonitrile-styrene-acrylate copolymer) engineering plastic, possessing good weather resistance, toughness, and dimensional stability, making it suitable for long-term outdoor monitoring.

[0030] See Figure 1 The measuring device includes a measuring ruler body 1 and a secondary ruler part 2. The measuring ruler body 1 is a long strip with a first end and a second end opposite to each other along its length. The secondary ruler part 2 is disposed at the first end of the measuring ruler body 1 and is integrally formed with the measuring ruler body 1. Its front surface is flush with the front surface of the measuring ruler body 1, together forming a continuous measuring surface. The front surface of the measuring ruler body has a main ruler scale marking 3, and the front surface of the secondary ruler part 2 has a secondary ruler scale marking 20. Two parallel long strip-shaped slits are provided on the secondary ruler part 2, namely a first through hole 21 and a second through hole 22. The first through hole 21 is wider, and its main function is to guide the measuring ruler body 1 to pass smoothly during installation. Its width is greater than the maximum distance between the ends of the two symmetrically arranged pawls 11 on the measuring ruler body 1, ensuring that the pawls 11 pass through without obstruction or deformation. The width of the second perforation 22 is slightly smaller, greater than the distance between the bases of the two symmetrically arranged pawls 11 on the main body of the measuring ruler 1, but less than the distance between the ends of the two pawls 11 (it is recommended that the slit width of the first perforation 21 be at least the scale body + 0.2 cm). This design allows the pawls 11 to elastically deform and pass through the second perforation 22 when the main body of the measuring ruler 1 is tightened. After rebounding, their ends lock onto the edge of the second perforation 22 away from the tree, achieving one-way locking and preventing the measuring ring from loosening. See details. Figure 3 .

[0031] In this embodiment, the starting graduation of the scale markings on the main body 1 of the measuring ruler connects with the graduation markings on the secondary scale 2 to form a continuous measuring scale. The front of the main body 1 has two rows of main scale graduation markings: the upper row is the diameter graduation marking 3a; the lower row is the corresponding circumference graduation marking 3b, facilitating direct reading. The starting point of the main scale graduation marking 33 extends from the first end of the main body 1 along the scale direction to the second end. The graduations of the main scale graduation marking 3 can be in centimeters, with the smallest graduation accurate to 0.1 centimeters. The secondary scale graduation marking 20 starts from the location of the second perforation 22 on the secondary scale 2 and proceeds towards the side of the secondary scale 2 away from its first perforation 21, marking from smallest to largest. When the second end of the measuring ruler 1 passes through the first perforation 21 and the second perforation 22 in sequence, the graduation marking of the main scale marking 3 at the second perforation 22 is the diameter reading, ensuring accurate measurement.

[0032] On both sides of the measuring scale body 1 in the width direction, pawl assemblies 10 are symmetrically arranged. Each pawl assembly 10 includes multiple pawls 11 arranged sequentially at intervals along the length direction of the scale. Each pawl 11 is a narrow strip, with its root connected to the side of the scale and its end extending outward at an angle A of 45°. The dimension of the pawl root in the length direction of the measuring scale body is denoted as h, and the distance between the roots of two adjacent pawls in the length direction of the measuring scale body is denoted as m. The values ​​of h and m are: 0.05cm≤h≤0.25cm; 0.05cm≤m≤0.25cm. The minimum scale size and the corresponding size of the pawl in the various figures of this utility model are only schematic and do not constitute a limitation based on the proportional relationship of the dimensions shown in these figures. In actual products, the scale markings of the measuring scale body and the auxiliary scale can be set according to the actual required size units. In some preferred embodiments, the dimension h of the pawl 11 root in the length direction of the measuring tape is 0.1 cm, the interval m between the roots of two adjacent pawls 11 is 0.1 cm, and the minimum scale size of the scale markings on the main body and auxiliary scale of the measuring tape is also 0.1 cm. The length L of the pawl 11 is 0.5 cm.

[0033] like Figure 3 As shown, the end of the pawl 11 in this embodiment is a standard straight edge structure (with a certain sharp corner). In a preferred embodiment, the end of the pawl 11 can be processed into an outwardly convex arc shape with a rounded corner diameter R = 0.1 cm, that is, a design without sharp edges and corners is adopted to prevent scratching the operator or damaging the bark.

[0034] On the back of the measuring ruler body 1 (i.e. the side that contacts the tree), a high-performance pressure-sensitive adhesive layer is coated. This adhesive layer is based on thermoplastic rubber (TPR) and has the characteristics of high initial tack, strong holding power, aging resistance and high and low temperature resistance. It can ensure that the measuring device is firmly attached to the tree trunk surface for a long time under various climatic conditions and is not easy to shift or fall off.

[0035] The method of using the measuring device in this embodiment is as follows: First, remove the protective film from the back of the device to expose the adhesive layer. Wrap the device around the tree trunk at a set height (e.g., 1.3 meters) and initially fix it with adhesive. Then, insert the second end (free end) of the measuring scale body 1 through the back of the auxiliary scale part 2 into the first perforation 21 (guide hole) and out through the second perforation 22 (locking hole). Hold the auxiliary scale part 2 with one hand and pull the free end of the measuring scale body 1 outwards with the other hand until the measuring ring is tightly against the tree trunk surface. At this time, the pawl 11 undergoes elastic deformation under the pulling force, allowing it to pass smoothly through the second perforation 22; when the pulling force is removed, the pawl 11 rebounds, and its end will lock onto the outer edge of the second perforation 22, forming a mechanical lock to prevent the scale from retracting. At this time, the initial diameter or circumference value can be read from the main scale graduation mark 3. In subsequent long-term monitoring, as the tree grows radially, the trunk will exert a continuous outward tightening force on the measuring ring. When the accumulated force is sufficient to overcome the locking force of pawl 11, pawl 11 itself will be squeezed by the edge of the second perforation 22, forcing the currently locked pawl 11 to "tilt in the opposite direction," thus slipping out of the current locking position. The measuring ring then expands slightly until the next (or several) pawls 11 again abut and lock against the edge of the second perforation 22, achieving a step-like, adaptive expansion of the measuring ring diameter, and the increased diameter at breast height (DBH) value can be read from the new locking position. This process requires no human intervention, enabling automatic, continuous, and accurate measurement of tree growth.

Claims

1. A device for measuring the radial growth period of trees, characterized in that: The measuring ruler includes a long, rectangular measuring ruler body (1) and a secondary measuring ruler part (2). The measuring ruler body (1) has a first end and a second end opposite each other in the length direction. The secondary measuring ruler part (2) is located at the first end of the measuring ruler body (1). The front of the secondary measuring ruler part (2) has a secondary measuring ruler scale mark (20), and the front of the measuring ruler body (1) has a main measuring ruler scale mark (3). The secondary measuring ruler part (2) has a first through hole (21) and a second through hole (22) arranged sequentially at intervals along its length direction. The two sides of the measuring ruler body (1) in the width direction each have a pawl assembly (10). Each pawl assembly (10) includes components arranged sequentially at intervals along the length direction of the measuring ruler body (1). Multiple pawls (11) are provided, each of which extends outward and is inclined toward the side where the first end of the measuring ruler body (1) is located. After the second end of the measuring ruler body (1) passes through the first perforation (21) and the second perforation (22) of the auxiliary ruler part (2) in sequence, the corresponding pawl (11) can be limited at the edge of the second perforation (22), so that the measuring ruler body (1) and the auxiliary ruler part (2) together form a measuring ring for being fitted around the tree to be measured and with an adjustable diameter. As the diameter at breast height of the tree to be measured increases, the corresponding pawl (11) on the measuring ruler body (1) can be pressed against the edge of the second perforation (22) and tilted in the opposite direction, so that the diameter of the measuring ring increases accordingly.

2. The tree radial growth long-term measurement device according to claim 1, characterized in that: The pawl assemblies (10) on both sides of the width direction of the measuring ruler body (1) are arranged symmetrically.

3. The tree radial growth long-term measurement device according to claim 2, characterized in that: The distance between the root positions of the two symmetrically arranged pawls on the main body of the measuring ruler is less than the width of the second through hole (22), and the distance between the end positions of the two symmetrically arranged pawls on the main body of the measuring ruler is greater than the width of the second through hole (22).

4. The tree radial growth long-term measurement device according to claim 3, characterized in that: The width of the first perforation (21) is greater than the distance between the end positions of the two pawls symmetrically arranged on the main body of the measuring ruler.

5. The long-term measuring device for radial growth of trees according to claim 1, characterized in that: The angle formed between the extension direction of the pawl (11) and the length direction of the measuring ruler body (1) is denoted as A, where the value of A is in the range of 40°≤A≤50°.

6. The long-term radial growth measurement device for trees according to claim 1, characterized in that: The length of the pawl (11) is denoted as L, and the value of L is in the range of 0.3cm≤L≤0.8cm.

7. The tree radial growth long-term measurement device according to claim 1, characterized in that: The dimension of the root of the pawl (11) along the length of the measuring ruler body (1) is denoted as h, and the distance between the roots of two adjacent pawls (11) along the length of the measuring ruler body (1) is denoted as m. The values ​​of h and m are as follows: 0.05cm≤h≤0.25cm; 0.05cm≤m≤0.25cm.

8. The tree radial growth long-term measuring device according to any one of claims 1 to 7, characterized in that: The main scale markings (3) on the main body (1) of the measuring ruler have two rows, one row being the diameter markings (3a) and the other row being the circumference markings (3b).

9. The tree radial growth long-term measuring device according to any one of claims 1 to 7, characterized in that: The back of the measuring ruler body (1) is provided with an adhesive layer for attaching the tree to be measured.

10. The tree radial growth long-term measuring device according to any one of claims 1 to 7, characterized in that: The end of each of the pawls (11) is a convex arc-shaped structure.

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