Adjustable fiber grating strain gauge welding device

Abstract

This utility model relates to an adjustable fiber optic strain gauge welding device, including a ruler, limiting blocks, a slider, and a locking mechanism. The slider is slidably installed at the center of the ruler. Limiting blocks are provided at the top and bottom of the slider, and both limiting blocks are slidably installed on the surface of the ruler. The locking mechanism is used to automatically lock the limiting blocks on the surface of the ruler. When in use, the limiting blocks are fixed according to the actual size of the welding body. During fixing, the elastic element is located inside the limiting block and applies a pushing force to the locking block, causing the locking block to engage with the locking groove, so that the locking block automatically engages with the locking groove on the surface of the ruler, realizing the quick locking of the limiting blocks without the need for manual tightening of bolts or other additional operations, improving the efficiency of adjustment and fixing. After the upper and lower limiting blocks are installed and fixed, the alignment slider is adjusted to the center position. After adjustment, it is fixed with side screws. After fixing, spot welding is performed on the four welding positioning holes on the surface of the slider.

Description

Technical Field

[0001] This utility model relates to the technical field of fiber optic strain gauge welding equipment, specifically an adjustable fiber optic strain gauge welding device. Background Technology

[0002] A fiber optic grating anchor gauge is a force measuring device that uses a fiber optic strain gauge welded to a load-bearing body. When an external load is applied to the load-bearing body, the body material undergoes elastic deformation, which causes the fiber optic strain gauge to deform. By measuring the strain data changes of the strain gauge, the actual force on the load-bearing body can be obtained.

[0003] Traditional fiber optic strain gauge welding is done manually, using marking and visual inspection for alignment, followed by laser cold welding for fixation. This manual method cannot ensure proper centering or fixation during welding, and it is difficult to achieve consistency when different strain gauges have different heights and sizes. Furthermore, there are inconsistencies in the manual alignment. Therefore, we need to provide an adjustable fiber optic strain gauge welding device. Utility Model Content

[0004] The purpose of this invention is to provide an adjustable fiber optic strain gauge welding device that can position the limiting block on the surface of the gauge without additional tools. When in use, the limiting block is fixed according to the actual size of the welding body. The limiting block is equipped with a locking mechanism that does not require manual adjustment and can achieve automatic locking, thus solving the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: an adjustable fiber optic strain gauge welding device, comprising:

[0006] The system includes a ruler strip, a limiting block, a slider, and a locking mechanism. The slider is slidably installed at the center of the ruler strip. The top and bottom of the slider are provided with limiting blocks, both of which are slidably installed on the surface of the ruler strip. The locking mechanism is used to automatically lock the limiting blocks to the surface of the ruler strip.

[0007] The locking mechanism includes a slot, an elastic element, and a locking block. The limiting block is provided with an elastic element for applying pressure to the locking block, and the surface of the ruler strip is provided with a slot that matches the end of the locking block.

[0008] Preferably, the elastic element includes a groove, a spring, and a limiting ring. The groove is formed inside the limiting block, the limiting ring is welded to the surface of the block, a spring is provided between the limiting ring and the groove, and the spring is movably sleeved on the surface of the block. The end of the block near the groove has an arc-shaped structure.

[0009] Preferably, the end of the card block away from the card slot passes through the surface of the limiting block and extends therefrom. A nut is threaded onto the surface of the card block, and the nut is used to fix the card block so that the card block does not contact the card slot.

[0010] Preferably, the side of the limiting block away from the locking mechanism is threaded with an abutment bolt for fixing the limiting block after fine adjustment.

[0011] Preferably, both sides of the slider are threaded with fixing bolts to fix the slider to the surface of the ruler.

[0012] Preferably, the slider is made of tungsten steel block, and two welding positioning holes are provided on both sides of the slider.

[0013] Preferably, the ruler strip is made of stainless steel, and the surface of the ruler strip has a scale groove with a 0.5mm graduation.

[0014] Preferably, the scale grooves and slots are distributed at intervals along the length of the ruler surface, and the positions of the slots correspond to the whole millimeter scale lines of the scale grooves.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] This invention allows for the positioning of the limiting block on the surface of the ruler without the need for additional tools. When in use, the limiting block is fixed according to the actual size of the welded body. The limiting block is equipped with a locking mechanism that eliminates the need for manual adjustment and enables automatic locking. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0018] Figure 2 This is a perspective view of the locking mechanism of this utility model;

[0019] Figure 3 This is a perspective view of the elastic element of this utility model;

[0020] Figure 4 This is a three-dimensional sectional view of the structure of this utility model.

[0021] In the diagram: 1. Ruler strip; 2. Limiting block; 3. Sliding block; 4. Locking mechanism; 41. Slot; 42. Block; 43. Elastic element; 431. Groove; 432. Spring; 433. Limiting ring; 5. Nut; 6. Abutting bolt; 7. Fixing bolt; 8. Welding positioning hole; 9. Scale groove. Detailed Implementation

[0022] 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.

[0023] Please see Figure 1-4 This utility model provides a technical solution: an adjustable fiber optic strain gauge welding device, comprising:

[0024] Ruler strip 1, limit block 2, slider 3 and locking mechanism 4. Slider 3 is slidably installed at the center of ruler strip 1. Limit blocks 2 are provided at the top and bottom of slider 3. Both limit blocks 2 are slidably installed on the surface of ruler strip 1. Locking mechanism 4 is used to automatically lock the limit blocks 2 on the surface of ruler strip 1.

[0025] The locking mechanism 4 includes a slot 41, an elastic element 43 and a block 42. The limiting block 2 is provided with an elastic element 43 for applying pressure to the block 42. The surface of the ruler 1 is provided with a slot 41 that matches the end of the block 42.

[0026] Specifically, the positioning of the limiting block 2 on the surface of the ruler strip 1 can be completed without additional tools. When in use, the limiting block 2 is fixed according to the actual size of the welded body. The limiting block 2 is equipped with a locking mechanism 4, which can achieve automatic locking without manual adjustment.

[0027] The elastic element 43 is located inside the limiting block 2 and applies a pushing force to the locking block 42, causing the locking block 42 to engage with the locking groove 41, so that the locking block 42 automatically engages with the locking groove 41 on the surface of the ruler 1, thereby achieving quick locking of the limiting block 2 without the need for manual tightening of bolts or other additional operations, thus improving the efficiency of adjustment and fixing.

[0028] The elastic element 43 includes a groove 431, a spring 432 and a limiting ring 433. The groove 431 is opened inside the limiting block 2. The limiting ring 433 is welded to the surface of the locking block 42. The spring 432 is provided between the limiting ring 433 and the groove 431, and the spring 432 is movably sleeved on the surface of the locking block 42. The end of the locking block 42 near the locking groove 41 has an arc-shaped structure.

[0029] Furthermore, the end of the locking block 42 adopts an arc-shaped structure, which facilitates smooth sliding into the slot 41 and reduces wear. The slot 41 is tapered, which allows the locking block 42 to automatically compress the spring 432 and disengage from the slot 41 when pushed by external force, achieving tool-free quick adjustment and more convenient operation. The limiting ring 433 is welded to the locking block 42 to ensure that the force of the spring 432 is evenly transmitted to the locking block 42. This elastic element 43 can push the locking block 42 into the slot 41 and apply pressure to ensure the stability of the limiting block 2. At the same time, the locking block 42 is made of wear-resistant material to extend its service life. The columnar part on one side of the limiting block 2 is part of the limiting block 2 and is a whole.

[0030] The movement of the limiting block 2 will cause the locking block 42 to move. The end of the locking block 42 is initially located in the slot 41. As the limiting block 2 is pressed, the arc-shaped end of the locking block 42 and the cone-shaped end in the slot 41 are pressed against each other, causing the locking block 42 to drive the limiting ring 433 to move. The limiting ring 433 compresses the spring 432, causing the locking block 42 to move until the arc-shaped end of the locking block 42 is pushed into another slot 41 by the spring 432, thus fixing the limiting block 2.

[0031] The end of the locking block 42 away from the slot 41 passes through the surface of the limiting block 2 and extends therefrom. A nut 5 is threaded on the surface of the locking block 42. The nut 5 is used to fix the locking block 42 so that the locking block 42 does not contact the slot 41.

[0032] It is worth noting that the extension of the locking block 42 is threaded with a nut 5, which can be manually pulled to separate the arc-shaped end of the locking block 42 from the locking groove 41. At this time, the nut 5 is rotated to fit against the columnar part on the surface of the limiting block 2. At this time, the limiting block 2 slides on the ruler 1 without resistance, and can be finely adjusted.

[0033] A contact bolt 6 is threaded on the side of the limit block 2 away from the locking mechanism 4 to fix the limit block 2 after fine adjustment;

[0034] Specifically, the abutment bolt 6 is threadedly installed inside the limit block 2, and the thread on the surface of the abutment bolt 6 has a self-locking function. The purpose is that when the limit block 2 slides without resistance and fine adjustment is made, the abutment bolt 6 is rotated to make one end of the abutment bolt 6 fit against the ruler 1, thereby fixing the limit ring 433 after fine adjustment. The abutment bolt 6 also has a self-locking function, and the self-locking thread design ensures that the position after fine adjustment will not be shifted due to vibration or operating force.

[0035] Both sides of the slider 3 are threaded with fixing bolts 7 to fix the slider 3 to the surface of the ruler strip 1;

[0036] Furthermore, slide the slider 3 on the ruler 1 to determine its position, then rotate the fixing bolts 7 on both sides of the slider 3. The ends of the fixing bolts 7 press against the ruler 1 to fix the slider 3. The threaded section of the bolt is coated with Loctite 243 thread-locking agent (medium strength, removable) to prevent the bolt from loosening due to welding vibration. A copper alloy washer (0.5mm thick, hardness ≥100HV) is installed between the bolt head and the slider 3 to avoid repeated tightening of the bolt, which would cause wear on the surface of the slider 3.

[0037] The slider 3 is made of tungsten steel, and two welding positioning holes 8 are opened on both sides of the slider 3;

[0038] It is worth noting that tungsten carbide is used to ensure that welding sparks do not damage the alignment holes. Tungsten carbide has a melting point as high as 3422℃, which is much higher than the laser welding temperature, and will not cause thermal deformation due to high temperature during welding (thermal expansion coefficient 4.5×10⁻). 6 / ℃, only 1 / 2 of that of stainless steel), ensuring the positioning hole spacing remains stable during welding (spacing error ≤0.01mm), avoiding strain gauge welding position deviation due to thermal expansion and contraction. After passivation treatment, the tungsten steel surface is not prone to rusting in humid environments (such as bridge monitoring sites), and the inner wall of the positioning hole remains smooth for a long time, preventing rust from affecting the welding quality (traditional carbon steel slider 3 shows rust after 3 months of use in an environment with humidity ≥80%, while tungsten steel slider 3 shows no obvious corrosion). Tungsten steel is a non-magnetic material (magnetic permeability ≈1), and will not interfere with the optical signal of the fiber optic grating (the magnetic field strength of traditional carbon steel slider 3 can reach 5-10mT, which may affect the wavelength drift measurement accuracy). When performing strain monitoring after welding, tungsten steel slider 3 will not introduce additional measurement errors. The inner wall of the positioning hole is ground (roughness Ra≤0.8μm), and the smooth surface can reduce spatter adhesion during welding (spatter removal efficiency is reduced from the traditional 30 minutes / piece to 5 minutes / piece), while avoiding hole blockage caused by spatter accumulation, ensuring that the positioning hole can still be used normally after multiple welding.

[0039] Ruler strip 1 is made of stainless steel, and the surface of ruler strip 1 has a scale groove 9 with a scale of 0.5mm.

[0040] It should be noted that stainless steel (such as grade 304) has a tensile strength ≥520MPa and a hardness ≥180HV, which is much higher than that of ordinary carbon steel (tensile strength ≥375MPa). The ruler 1 is less prone to plastic deformation when the limit block 2 is frequently adjusted (the bending degree of traditional Q235 carbon steel ruler 1 is ≥0.5mm after 1000 uses, while the bending degree of stainless steel ruler 1 is ≤0.1mm after 100,000 uses), ensuring the long-term stability of the scale groove 9.

[0041] The scale grooves 9 and the slots 41 are distributed at intervals along the length of the ruler strip 1, and the positions of the slots 41 correspond to the whole millimeter scale lines of the scale grooves 9.

[0042] The scale groove 9 provides 0.5mm subdivision scales to achieve "visual quantitative adjustment". When the operator pushes the limit block 2, the correspondence between the slot 41 and the whole millimeter scale line can be quickly identified through the scale groove 9 (such as the scale line at the position of the slot 41 being thickened). When the block 42 approaches the slot 41 (such as the scale display of 10.0mm), the moving distance can be precisely controlled.

[0043] All threaded structures involved in this application have a self-locking function, using ordinary triangular threads (60° thread angle). The thread helix angle (λ) is less than the equivalent friction angle (ρv) of the screw pair. Self-locking is usually achieved when λ≤3°-4° (e.g., M5 thread pitch 0.8mm, pitch diameter 5mm, helix angle λ=arctan (0.8 / π×5)≈2.9°<ρv≈5°). This ensures that the bolts do not loosen during welding vibration (frequency 50-200Hz). The surface is coated to prevent the adhesion of foreign matter. The coating is made of polytetrafluoroethylene (PTFE) (thickness 5-10μm), with a surface roughness Ra≤0.4μm and a friction coefficient ≤0.1, which can prevent the adhesion of foreign matter such as metal shavings and welding spatter.

[0044] This device features an adjustable and movable upper and lower limit blocks 2. When in use, the limit blocks 2 are fixed according to the actual dimensions of the welding body. During fixation, the elastic element 43 is located inside the limit blocks 2, applying a pushing force to the locking block 42, which engages with the locking slot 41, allowing the locking block 42 to automatically engage with the locking slot 41 on the surface of the ruler 1, thus achieving rapid locking of the limit blocks 2 without the need for manual tightening of bolts or other additional operations, improving the efficiency of adjustment and fixation. After the upper and lower limit blocks 2 are installed and fixed, the alignment slider 3 is adjusted to the center position. After adjustment, it is fixed with the side top screw. After fixation, spot welding is performed on the four welding positioning holes 8 on the surface of the slider 3. The four welding positioning holes 8 correspond to the welding points of the fiber optic strain gauge. During use, the position can be adjusted directly according to the scale to achieve precise position limiting.

[0045] 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. An adjustable fiber optic strain gauge welding device, characterized in that, include: Ruler strip (1), limiting block (2), slider (3) and locking mechanism (4), the slider (3) is slidably installed at the center of the ruler strip (1), the top and bottom of the slider (3) are provided with limiting blocks (2), the two limiting blocks (2) are slidably installed on the surface of the ruler strip (1), and the locking mechanism (4) is used to automatically lock the limiting blocks (2) on the surface of the ruler strip (1); The locking mechanism (4) includes a slot (41), an elastic element (43) and a block (42). The limiting block (2) is provided with an elastic element (43) for applying pressure to the block (42). The surface of the ruler (1) is provided with a slot (41) that is adapted to the end of the block (42).

2. The adjustable fiber optic strain gauge welding device according to claim 1, characterized in that: The elastic element (43) includes a groove (431), a spring (432) and a limiting ring (433). The groove (431) is opened inside the limiting block (2). The limiting ring (433) is welded to the surface of the locking block (42). A spring (432) is provided between the limiting ring (433) and the groove (431), and the spring (432) is movably sleeved on the surface of the locking block (42). The end of the locking block (42) near the slot (41) has an arc-shaped structure.

3. The adjustable fiber optic strain gauge welding device according to claim 2, characterized in that: The end of the card block (42) away from the card slot (41) passes through the surface of the limiting block (2) and extends thereto. A nut (5) is threaded onto the surface of the card block (42). The nut (5) is used to fix the card block (42) so that the card block (42) does not contact the card slot (41).

4. The adjustable fiber optic strain gauge welding device according to claim 1, characterized in that: The limiting block (2) has a threaded abutment bolt (6) on the side of its surface away from the locking mechanism (4) for fixing the limiting block (2) after fine adjustment.

5. The adjustable fiber optic strain gauge welding device according to claim 1, characterized in that: Both sides of the slider (3) are threaded with fixing bolts (7) to fix the slider (3) to the surface of the ruler (1).

6. The adjustable fiber optic strain gauge welding device according to claim 5, characterized in that: The slider (3) is made of tungsten steel block, and two welding positioning holes (8) are opened on both sides of the slider (3).

7. The adjustable fiber optic strain gauge welding device according to claim 1, characterized in that: The ruler strip (1) is made of stainless steel, and the surface of the ruler strip (1) is provided with a scale groove (9) with a scale of 0.5mm.

8. The adjustable fiber optic strain gauge welding device according to claim 7, characterized in that: The scale groove (9) and the slot (41) are distributed at intervals along the length direction on the surface of the ruler (1), and the position of the slot (41) corresponds to the whole millimeter scale line of the scale groove (9).

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