High-precision small-range fiber grating crack meter

Abstract

The utility model relates to a kind of high-precision small range fiber grating crack meter, including sensitive element shell, the left end of the sensitive element shell is fixedly installed with import piece, the inside of the import piece is worn with optical fiber piece, the right end of the sensitive element shell is fixedly installed with link cylinder, the side of the link cylinder away from sensitive element shell is fixedly installed with adjusting cylinder. The high-precision small range fiber grating crack meter, by setting adjusting assembly, when adjusting spring telescopic degree, after opening sealing plate, manually fixedly moving plate avoids interference, then rotates knob, is driven moving cylinder horizontal movement by worm, worm wheel, rotation shaft and threaded shaft transmission, changes the distance between adjusting plate and moving plate to adjust spring telescopic range, finally loosens moving plate, the setting can be flexibly adapted according to initial crack width, when width is too large, increase range avoids insufficiently tight, when width is too small, reduce range prevents spring excessive compression, both solve the problem of fixed range spring adaptability.

Description

Technical Field

[0001] This utility model relates to the field of engineering technology, specifically a high-precision, small-range fiber optic grating crack gauge. Background Technology

[0002] The crack gauge is a sensor based on the inductively modulated frequency principle. It has a built-in electronic tag, which can be customized, directly outputs physical quantities, and can store up to 1600 data points. This type of product offers high accuracy and stability, and can be used for long-term observation via manual reading or automatic data acquisition. It is used to measure changes in expansion joints or cracks in various structures and is widely applied in engineering fields such as highways, railways, bridges, dams, tunnels, slopes, and buildings. The appropriate product should be selected based on the site conditions and required accuracy.

[0003] A search revealed, for example, a high-precision fiber optic crack gauge disclosed in Chinese Utility Model Patent Publication No. CN209673050U. This device, by placing a rubber ring inside the inlet, prevents damage to the connection point during fiber optic connection and ensures the stability of the connection between the fiber optic cable and the crack gauge, avoiding measurement results affected by connection problems. It employs the fiber optic grating sensing principle, accurately capturing wavelength changes caused by crack opening and closing. After analysis by a demodulator, it accurately outputs the displacement change, ensuring reliable measurement accuracy.

[0004] However, the return spring of this device has a fixed extension length, which cannot be flexibly adjusted according to different initial crack widths. When the initial crack width is too large or too small, it is easy to have insufficient tightening or excessive compression, which will affect the measurement accuracy and equipment life. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a high-precision, small-range fiber optic crack gauge with an adjustable return spring length to flexibly adapt to different initial cracks.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a high-precision, small-range fiber optic grating crack gauge, comprising a sensitive element housing, an inlet component fixedly installed at the left end of the sensitive element housing, an optical fiber component passing through the inlet component, a connecting cylinder fixedly installed at the right end of the sensitive element housing, an adjusting cylinder fixedly installed on the side of the connecting cylinder away from the sensitive element housing, a cover plate provided on the right side of the adjusting cylinder, and an adjusting assembly provided inside the adjusting cylinder; The adjusting assembly includes a movable plate slidably mounted inside the adjusting cylinder. A connecting rod is fixedly mounted on the side of the movable plate facing the cover plate, and a return spring is fixedly mounted on the side of the movable plate away from the connecting rod. An adjusting plate is fixedly mounted on the side of the return spring away from the movable plate. A worm gear is rotatably mounted on the bottom wall of the adjusting cylinder. A worm wheel meshes with the top tooth surface of the worm gear. A rotating shaft is fixedly mounted in the middle of the worm wheel. A threaded shaft is fixedly mounted on the right end of the rotating shaft. The movable cylinder is fixedly mounted on the side of the threaded shaft away from the rotating shaft.

[0007] Furthermore, a rubber ring is fixedly installed around the center of the inner wall of the imported component.

[0008] Furthermore, a sealing plate is fixedly installed on the front surface of the adjusting cylinder by bolts.

[0009] Furthermore, the top and bottom side walls of the adjusting cylinder are provided with slide rails, and a movable plate is slidably installed on the adjusting cylinder via the slide rails. The right wall of the adjusting cylinder is provided with an opening that can accommodate the connecting rod to enter and exit.

[0010] Furthermore, the adjusting plate is slidably disposed inside the adjusting cylinder, and the rotating shaft is rotatably mounted to the inner right wall of the adjusting cylinder.

[0011] Furthermore, a knob is fixedly installed on the front side of the worm gear, an adjustment plate is fixedly installed on the right side of the moving cylinder, and a nut is threadedly connected to the surface of the threaded shaft, with the nut located at the threaded connection between the moving cylinder and the threaded shaft.

[0012] Compared with the prior art, the technical solution of this application has the following beneficial effects: This high-precision, small-range fiber optic crack gauge features an adjustment mechanism. When adjusting the spring's extension / retraction, the sealing plate is opened, and the moving plate is manually fixed to prevent interference. Then, rotating the knob drives the moving cylinder horizontally via a worm gear, worm wheel, rotating shaft, and threaded shaft, changing the distance between the adjustment plate and the moving plate to adjust the spring's extension / retraction range. Finally, the moving plate is released. This setting can flexibly adapt to the initial crack width—increasing the range when the width is too large to avoid insufficient tightening, and decreasing the range when the width is too small to prevent excessive spring compression. This solves the problem of poor adaptability of fixed-range springs and improves measurement accuracy. Attached Figure Description

[0013] Figure 1 This is a perspective view of the present utility model; Figure 2 This is a front sectional view of the adjusting cylinder of this utility model; Figure 3 This utility model Figure 2 Enlarged view of point A in the middle; Figure 4 This is a perspective view of the imported component of this utility model.

[0014] In the diagram: 1. Sensitive element housing; 2. Imported component; 3. Rubber ring; 4. Fiber optic component; 5. Connecting cylinder; 6. Adjusting cylinder; 7. Cover plate; 8. Sealing plate; 9. Adjusting assembly; 901. Moving plate; 902. Connecting rod; 903. Return spring; 904. Adjusting plate; 905. Worm gear; 906. Knob; 907. Worm wheel; 908. Rotating shaft; 909. Threaded shaft; 910. Moving cylinder; 911. Nut. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Please see Figure 1-4 A high-precision, small-range fiber optic grating crack gauge in this embodiment includes a sensitive element housing 1, an inlet component 2 fixedly installed at the left end of the sensitive element housing 1, an optical fiber component 4 passing through the inside of the inlet component 2, a connecting cylinder 5 fixedly installed at the right end of the sensitive element housing 1, an adjusting cylinder 6 fixedly installed on the side of the connecting cylinder 5 away from the sensitive element housing 1, a cover plate 7 provided on the right side of the adjusting cylinder 6, and an adjusting component 9 provided inside the adjusting cylinder 6. The adjusting assembly 9 includes a movable plate 901, which is slidably installed inside the adjusting cylinder 6. A connecting rod 902 is fixedly installed on the side of the movable plate 901 facing the cover plate 7. A return spring 903 is fixedly installed on the side of the movable plate 901 away from the connecting rod 902. An adjusting plate 904 is fixedly installed on the side of the return spring 903 away from the movable plate 901. A worm gear 905 is rotatably installed on the bottom wall of the adjusting cylinder 6. A worm wheel 907 meshes with the top tooth surface of the worm gear 905. A rotating shaft 908 is fixedly installed in the middle of the worm wheel 907. A threaded shaft 909 is fixedly installed at the right end of the rotating shaft 908. A movable cylinder 910 is fixedly installed on the side of the threaded shaft 909 away from the rotating shaft 908.

[0017] like Figure 1 and Figure 4 As shown, by setting the rubber ring 3, the elastic tension of the rubber can be used to tightly wrap the inserted optical fiber, effectively limiting the radial movement of the optical fiber inside the inlet component 2, avoiding the loosening of the optical fiber connector due to equipment vibration or slight pulling, and ensuring the stability of the connection between the optical fiber and the sensitive element; at the same time, it can form a buffer protection during the optical fiber insertion process, reducing the direct friction between the optical fiber and the inner wall of the inlet component 2, preventing the outer sheath of the optical fiber from being worn or broken, and extending the service life of the optical fiber.

[0018] like Figure 1 As shown, by setting the sealing plate 8, the components inside the regulating cylinder 6 can be sealed and protected when the regulating component 9 is not in use, thereby preventing dust from entering the interior of the regulating cylinder 6.

[0019] like Figure 2 As shown, by setting a slide rail, the movable plate 901 can move stably inside the adjusting cylinder 6, avoiding deviation and jamming of the movable plate 901 during movement. It should be noted that when adjusting the extension and retraction stroke of the spring, the movable plate 901 can be manually limited to prevent affecting the adjustment of the spring extension and retraction stroke.

[0020] like Figure 3 As shown, by setting nut 911, the tightness of the connection between threaded shaft 909 and moving cylinder 910 can be enhanced, preventing them from loosening during long-term use of the equipment or in a vibrating environment, ensuring the stability of the spring extension range after adjustment, and avoiding measurement deviation due to connection gap; at the same time, the locking effect of nut 911 can fix the adjusted position, ensuring that the spring preload remains constant.

[0021] When implementing this procedure, please follow these steps: 1) When it is necessary to adjust the spring extension and retraction, first open the sealing plate 8 of the equipment, and then manually fix the moving plate 901 to prevent the moving plate 901 from moving accidentally during the adjustment process, and ensure that the spring extension and retraction stroke adjustment is not disturbed. 2) Then rotate knob 906. Knob 906 drives worm 905 to rotate. Worm 905 meshes with worm wheel 907 for transmission, which in turn drives rotating shaft 908 and threaded shaft 909 to rotate synchronously. 3) When the threaded shaft 909 rotates, it drives the movable cylinder 910 sleeved on it to move horizontally. By changing the distance between the adjusting plate 904 and the movable plate 901, the extension range of the spring can be adjusted. 4) Finally, loosen the manually fixed moving plate 901 to complete the adjustment process. When the initial crack width is too large, increase the spring extension range to avoid insufficient clamping and ensure accurate displacement transmission; when the initial crack width is too small, reduce the spring extension range to prevent excessive compression and reduce the risk of elastic failure. This adapts to diverse crack scenarios and improves the accuracy of measurement data.

[0022] In summary, this high-precision, small-range fiber optic crack gauge, through the setting of adjustment component 9, allows for the adjustment of the spring extension range. After opening the sealing plate 8, the moving plate 901 is manually fixed to avoid interference. Then, rotating the knob 906 drives the moving cylinder 910 to move horizontally via the worm gear 905, worm wheel 907, rotating shaft 908, and threaded shaft 909, changing the distance between the adjustment plate 904 and the moving plate 901 to adjust the spring extension range. Finally, the moving plate 901 is released. This setting can be flexibly adapted to the initial crack width—increasing the range when the width is too large to avoid insufficient tightening, and reducing the range when the width is too small to prevent excessive spring compression. This solves the problem of poor adaptability of fixed-range springs and improves measurement accuracy.

[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0024] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-precision, small-range fiber optic crack gauge, comprising a housing of a sensing element (1), characterized in that: An inlet component (2) is fixedly installed on the left end of the housing (1) of the sensitive element. An optical fiber component (4) is inserted inside the inlet component (2). A connecting tube (5) is fixedly installed on the right end of the housing (1) of the sensitive element. An adjusting tube (6) is fixedly installed on the side of the connecting tube (5) away from the housing (1) of the sensitive element. A cover plate (7) is provided on the right side of the adjusting tube (6). An adjusting component (9) is provided inside the adjusting tube (6). The adjusting assembly (9) includes a movable plate (901), which is slidably installed inside the adjusting cylinder (6). A connecting rod (902) is fixedly installed on the side of the movable plate (901) facing the cover plate (7). A return spring (903) is fixedly installed on the side of the movable plate (901) away from the connecting rod (902). An adjusting plate (904) is fixedly installed on the side of the return spring (903) away from the movable plate (901). A worm gear (905) is rotatably installed on the bottom wall of the adjusting cylinder (6). A worm wheel (907) meshes with the top tooth surface of the worm gear (905). A rotating shaft (908) is fixedly installed in the middle of the worm wheel (907). A threaded shaft (909) is fixedly installed at the right end of the rotating shaft (908). A movable cylinder (910) is fixedly installed on the side of the threaded shaft (909) away from the rotating shaft (908).

2. The high-precision, small-range fiber optic crack gauge according to claim 1, characterized in that: A rubber ring (3) is fixedly installed around the center of the inner wall of the imported part (2).

3. The high-precision, small-range fiber optic crack gauge according to claim 1, characterized in that: A sealing plate (8) is fixedly installed on the front surface of the regulating cylinder (6) by bolts.

4. The high-precision, small-range fiber optic crack gauge according to claim 1, characterized in that: The top and bottom side walls of the regulating cylinder (6) are provided with slide rails. The regulating cylinder (6) is slidably mounted with a moving plate (901) via the slide rails. The right wall of the regulating cylinder (6) is provided with an opening that can accommodate the connecting rod (902) to enter and exit.

5. A high-precision, small-range fiber optic crack gauge according to claim 1, characterized in that: The adjusting plate (904) is slidably disposed inside the adjusting cylinder (6), and the rotating shaft (908) is rotatably installed on the inner right wall of the adjusting cylinder (6).

6. A high-precision, small-range fiber optic crack gauge according to claim 1, characterized in that: A knob (906) is fixedly installed on the front side of the worm (905), an adjusting plate (904) is fixedly installed on the right side of the moving cylinder (910), a nut (911) is threadedly connected to the surface of the threaded shaft (909), the nut (911) is located at the threaded connection between the moving cylinder (910) and the threaded shaft (909), and a cover plate (7) is fixedly installed on the side of the connecting rod (902) away from the moving plate (901).

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