Steel bar meter convenient to use
By using a split structure and precision threaded connection, the coaxiality problem of the sensor during the welding process of the rebar gauge is solved, ensuring the coaxiality of the measuring part and the strain part, and improving the measurement accuracy and long-term stability of the sensor.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBEI FANGFANG TECH CO LTD
- Filing Date
- 2025-06-22
- Publication Date
- 2026-04-24
AI Technical Summary
Existing rebar gauges are prone to slight angular deviations between the sensor body and the rebar axis due to high temperature and thermal deformation during welding, resulting in distorted measurement results. Furthermore, traditional installation methods cannot guarantee the coaxiality of the measuring unit and the strain gauge.
The strain gauge and the measuring part are welded separately. After the strain gauge is welded independently, it is precisely threaded to the measuring part through a connecting mechanism. The guiding and locking mechanism of the threaded connection ensures coaxiality and forms a multi-point constrained connection.
It effectively reduces the risk of misalignment between the measuring part and the steel bar axis caused by welding heat effect, improves measurement accuracy and long-term stability, ensures the authenticity of stress transfer and data accuracy, and reduces the probability of early failure of connection points.
Smart Images
Figure CN224163211U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of steel reinforcement engineering measurement technology, and more specifically, to a convenient steel reinforcement meter. Background Technology
[0002] A rebar stress gauge, also known as a rebar stress meter, is a sensor specifically designed for direct embedding within concrete structures to monitor the stress / strain state of reinforcing bars (or prestressed steel strands) over long periods and in real time. It is a key sensing element in structural health monitoring (SHM) and safety early warning systems. Its core function is to convert the mechanical forces (tensile and compressive stresses and their changes) acting on the rebar into measurable electrical signals (such as frequency, resistance, and voltage) or changes in physical quantities, providing in-situ, direct data for assessing the structural stress state, safety performance, and durability.
[0003] Vibrating wire rebar gauges are one of the core sensors for monitoring the stress in the reinforcing bars of concrete structures. Their working principle is based on the physical characteristic that the vibration frequency of the internally tensioned steel wire varies with the axial tensile / compressive stress. To accurately reflect the stress state of the reinforcing bars, the gauge must be an integrated segment along the stress path. Currently, the most common installation method is to weld the gauge between the end faces of two sections of the reinforcing bars to be measured. The core requirement of this installation method is that the gauge must be strictly aligned with the connected reinforcing bars on the same axis (i.e., coaxial). Only when this condition is met can the axial force borne by the reinforcing bars be transmitted through the gauge without distortion or additional bending stress. The internal vibrating wire then senses the pure axial stress, and the measurement result truly represents the actual stress state of the reinforcing bars at that location. However, a critical structural problem commonly exists in practical installations: existing installations only connect the strain gauge rigid body via threaded connections. The high temperature and thermal deformation generated during welding can easily cause uncontrollable micro-angular deviations between the sensor body and the reinforcing bar axis, leading to misalignment.
[0004] The purpose of this utility model is to provide a convenient rebar gauge to solve the problems existing in the prior art. Utility Model Content
[0005] To achieve the above objectives, this utility model provides the following solution:
[0006] This utility model provides a convenient rebar gauge, comprising:
[0007] The rebar gauge structure includes a measuring part and a strain gauge. The strain gauge is located at both ends of the measuring part and is locked to the measuring part through a connecting mechanism. Both ends of the measuring part are provided with locking mechanisms. The connecting mechanism is fixedly connected to the strain gauge. One end of the strain gauge is provided with a threaded protrusion, and one end of the connecting mechanism is provided with a threaded groove. The threaded protrusion corresponds to the threaded groove. The strain gauge is threadedly connected to the connecting mechanism.
[0008] Furthermore, the measuring unit includes an induction coil, a measuring housing, a strain gauge, a thermometer, and a connector. The measuring housing has a hollow structure, the strain gauge is located inside the measuring housing, the induction coil is located on one side of the middle of the strain gauge, and a thermometer is installed inside the measuring housing. The induction coil, the strain gauge, and the thermometer are all electrically connected to the connector.
[0009] Furthermore, the strain unit includes a strain rigid body, the diameter of which is larger than that of the rigid body to be measured, and the diameter of the strain rigid body corresponds to that of the connecting mechanism.
[0010] Furthermore, the connecting mechanism includes a connector, a first groove, a first blocking member, a second blocking member, and a first rotating head. One end of the connector is provided with the threaded groove, and the end of the connector away from the threaded groove is provided with the first rotating head. The diameter of the connector corresponds to the locking mechanism. The outer wall of the connector is provided with an annular first groove. The first blocking member and the second blocking member are provided on both sides of the first groove. A first inclined surface is formed between the first groove, the first blocking member, and the second blocking member.
[0011] Furthermore, the first rotating head is threaded, and the length of the first blocking member is greater than that of the second blocking member.
[0012] Furthermore, the locking mechanism includes a first locking groove, a second locking groove, a locking bead, a second groove, and a threaded groove. The second locking groove is fixedly connected to the measuring housing, and the first locking groove is fixedly connected to the second locking groove. The diameter of the second locking groove is smaller than that of the first locking groove, and a second inclined surface is formed between the second locking groove and the first locking groove. A plurality of second grooves are circumferentially formed on the first locking groove, and a locking bead is disposed in the second groove. A threaded groove is formed on the bottom wall of the second locking groove.
[0013] Furthermore, the size of the second groove corresponds to the locking bead, and the size of the locking bead corresponds to the first groove, while the size of the threaded groove corresponds to the first rotating head.
[0014] Compared with existing technologies, the advantages of this invention are as follows: By isolating the strain gauge, the core of the stress-bearing structure, this invention allows it to be welded to the reinforcing bar face-to-face independently. Because the strain gauge structure is relatively simple and lacks precision measuring elements, the heat and deformation generated during welding have a relatively small impact on its own axis, and the operator can focus more on ensuring the precise alignment of the strain gauge and the reinforcing bar. After the strain gauge is firmly welded, the measuring part is precisely assembled onto it through a connecting mechanism. This solves the problem of traditional reinforcing bar gauges having fixed, thickened strain gauge bodies at both ends, requiring overall butt welding to the reinforcing bar. The high temperature and thermal deformation generated during welding easily lead to uncontrollable micro-angular deviations between the sensor body and the reinforcing bar axis, resulting in misalignment. The precise threaded connection between the connecting mechanism (with a threaded groove on one end) and the strain gauge (with a threaded protrusion on one end) inherently provides guidance and positioning functions. The locking mechanisms at both ends of the measuring part provide final tightening of the connecting mechanism, forming a rigid, multi-point constrained connection. This design effectively prevents any slight wobbling or displacement of the strain gauge during the final tightening process, ensuring that the axis of the measuring unit is strictly coincident with the axis of the welded and fixed strain gauge. Therefore, it fundamentally reduces the risk of misalignment (non-axis) between the measuring unit and the overall reinforcing steel axis caused by welding heat and installation disturbances, guaranteeing the authenticity of axial stress transmission and the accuracy of measurement data. The high temperature during welding is one of the main threats to precision sensors (such as vibrating wires and electronic components). While the high welding temperature only affects the individual strain gauge, the measuring unit, containing all precision measuring elements, is assembled at room temperature via a connecting mechanism after welding cooling. This isolates the direct and indirect (heat conduction) effects of the high welding temperature on the core sensitive elements of the measuring unit, improving the initial measurement accuracy and long-term stability of the sensor and reducing the probability of early failure due to welding heat damage. The threaded connection itself possesses good tensile and compressive strength. The threaded engagement between the connecting mechanism and the strain unit, along with the final tightening of the connecting mechanism by the locking mechanism, together form a multi-layered mechanical locking structure. This enhances the connection stiffness and integrity of the entire sensor along the stress path of the reinforcing steel, reduces the risk of fretting wear, loosening, or even failure at the connection points during long-term service, especially under alternating or impact loads, and ensures the continuity and reliability of the stress transmission path. Attached Figure Description
[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:
[0016] Figure 1 A schematic diagram of a convenient rebar gauge provided in this embodiment of the present invention;
[0017] Figure 2A cross-sectional view of the measuring section in a convenient rebar gauge provided in this embodiment of the utility model;
[0018] Figure 3 Side view of the locking structure in a convenient rebar gauge provided in this embodiment of the utility model;
[0019] Figure 4 A side view of the connecting mechanism in a convenient rebar meter provided in this embodiment of the utility model.
[0020] The structure includes: 1. Reinforcement gauge structure; 101. Measuring part; 1011. Induction coil; 1012. Measuring housing; 1013. Strain gauge needle; 1014. Thermometer; 1015. Connector; 102. Strain rigid body; 2. Connecting structure; 201. Threaded groove; 202. Connector head; 203. First groove; 204. First blocking element; 205. Second blocking element; 206. First rotating head; 207. First inclined surface; 3. Locking structure; 301. First locking groove; 302. Second locking groove; 303. Locking ball; 304. Second groove; 305. Threaded groove. Detailed Implementation
[0021] The embodiments of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0022] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0023] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0024] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0025] See Figure 1-2 As shown, this embodiment provides a convenient rebar gauge, including:
[0026] The rebar gauge structure 1 includes a measuring part 101 and a strain gauge. The strain gauge is located at both ends of the measuring part 101. The strain gauge is locked to the measuring part 101 through a connecting mechanism. Both ends of the measuring part 101 are provided with locking mechanisms. The connecting mechanism is fixedly connected to the strain gauge. One end of the strain gauge is provided with a threaded protrusion. One end of the connecting mechanism is provided with a threaded groove 305. The threaded protrusion corresponds to the threaded groove 305. The strain gauge is threadedly connected to the connecting mechanism.
[0027] Specifically, when welding is required, the strain gauge can be welded to the reinforcing bar to be tested first. After welding, the strain gauge is connected to the connecting mechanism, and then the connecting mechanism is connected to the locking mechanism to achieve the measurement effect. Alternatively, the strain gauge can be connected to the locking mechanism first, and then welded. Common welding methods include welding the end face of the strain gauge to the reinforcing bar to be tested, or placing the strain gauge on one side of the reinforcing bar to be tested and connecting it by welding the side. Both methods can be applied in this embodiment. When welding the end face, one end of the strain gauge can be connected to the locking structure 3 first through the connecting mechanism. Weld one side first, and then weld the other side after the temperature drops. This embodiment is flexible and can be applied to various welding connection methods. Furthermore, the locking connection through the locking mechanism and the connecting mechanism can also prevent the strain gauge from shaking and reduce the possibility of misalignment.
[0028] It is understandable that traditional integral welding is prone to causing the sensor and reinforcing bar axis to shift due to thermal deformation or operational errors. This embodiment uses a separate structure, allowing the strain unit to be independently welded and fixed, eliminating positional interference of the measuring unit 101 during the welding process. After welding, a precision threaded connection mechanism locks the strain unit and measuring unit 101 together. Utilizing the self-guiding nature of the thread and the rigid constraint of the locking mechanism, coaxial positioning of the strain unit and measuring unit 101 is forcibly achieved. This reduces the risk of angular deviation caused by welding thermal stress or installation vibration, improving the accuracy of axial stress transmission and the reliability of measurement data. The threaded groove 305 of the connection mechanism and the threaded protrusion of the strain unit form the first layer of anti-torsional constraint. The axial compression of the connection mechanism by the locking mechanism provides the second layer of tensile / compressive constraint. This double-locking structure strengthens the mechanical coupling between the measuring unit 101 and the strain unit, reducing the possibility of loosening due to vibration or load impact during service, ensuring the continuity and stability of the stress transmission path. This embodiment is compatible with both end-face welding and side-welding processes.
[0029] **Pre-weld-then-assemble mode:** The strain gauges at both ends are individually welded to the reinforcing bars. After cooling, the measuring unit 101 is assembled, isolating the high-temperature welding from the thermal impact on the measuring unit 101 and improving the initial accuracy and lifespan of the sensor. **Pre-assemble-then-weld mode:** The strain gauges are pre-assembled with the measuring unit 101 via a connecting mechanism, and then the sides of the strain gauges are welded to the reinforcing bars. This simplifies the on-site alignment process and is particularly suitable for space-constrained scenarios. In end-face welding scenarios, one end of the strain gauge and measuring unit 101 can be assembled and locked first, and then the other end can be processed after cooling. This step-by-step operation avoids the heat accumulation effect of simultaneous welding on both sides, reduces the risk of overall structural deformation due to uneven thermal expansion, and ensures the final straightness of the axis. The measuring unit 101 (including precision units such as vibrating wires / circuits) is completely isolated from the high-temperature welding zone. Through physical isolation, it completely avoids component performance drift, insulation aging, or sealing failure caused by thermal effects, improving the long-term stability and measurement consistency of the sensor. As an independent welding unit, the strain gauge can be made of materials with high welding compatibility (such as low-carbon steel), avoiding the problem of compromising the mechanical properties of the welded area in traditional integrated structures due to the need to consider measurement performance. This structure optimizes the fatigue resistance and brittle fracture resistance of the welded area, reducing the probability that the connection point will become a weak point in the structure.
[0030] In some embodiments of this application, the measuring unit 101 includes an induction coil 1011, a measuring housing 1012, a strain gauge 1013, a thermometer 1014, and a connector 1015. The measuring housing 1012 has a hollow structure. The strain gauge 1013 is located inside the measuring housing 1012. The induction coil 1011 is located on one side of the middle of the strain gauge 1013. The thermometer 1014 is also provided inside the measuring housing 1012. The induction coil 1011, the strain gauge 1013, and the thermometer 1014 are all electrically connected to the connector 1015. A cable is connected to the connector 1015 to realize the measurement.
[0031] In some embodiments of this application, the strain section includes a strain rigid body 102, the diameter of which is larger than that of the rigid body to be measured, and the diameter of the strain rigid body 102 corresponds to the connecting mechanism.
[0032] Understandably, the strain gauge 1013, as the core mechanical sensing unit, is axially positioned at the center of the inner cavity of the measuring housing 1012, ensuring that the stress transmission path coincides with the housing axis, thus improving the symmetry and representativeness of strain detection. The thermometer 1014 is directly built into the measuring housing 1012, sensing the temperature changes of the microenvironment in which the sensor is located in real time, eliminating the temperature measurement deviation caused by the difference in the installation position of the external thermometer 1014. Combined with strain data, it can automatically compensate for the thermal expansion and contraction effect caused by temperature, reducing the risk of measurement distortion caused by environmental interference. The induction coil 1011 is located on one side of the middle of the strain gauge 1013, optimizing the magnetic field distribution to accurately capture the frequency change of the vibrating wire. This improves the electromagnetic signal conversion efficiency and enhances the sensitivity of micro-strain identification. The measuring housing 1012 provides a rigid physical barrier for the strain gauge 1013, induction coil 1011, and thermometer 1014, preventing direct damage to the internal components from concrete pouring pressure and external mechanical impact. The thickened strain rigid body 102 has a diameter larger than the steel bar being measured. By increasing the cross-sectional area, it compensates for the potential local strength reduction caused by the hollow internal structure, ensuring that the yield strength of the strain section is not lower than that of the steel bar under extreme loads, thus preventing the sensor from becoming a weak link in the stress chain. Its diameter matches the connecting mechanism, providing sufficient wall thickness for the threaded protrusions, enhancing the shear resistance and deformation resistance of the threaded connection area, and reducing the risk of thread engagement failure under high stress conditions. The strain rigid body 102 directly contacts the strain needle 1013 through the connecting mechanism.
[0033] In some embodiments of this application, see Figure 3-4As shown, the connecting mechanism includes a connector 202, a first groove 203, a first blocking member 204, a second blocking member 205, and a first rotating head 206. One end of the connector 202 is provided with a threaded groove 305, and the end of the connector 202 away from the threaded groove 305 is provided with the first rotating head 206. The diameter of the connector 202 corresponds to the locking mechanism. The outer wall of the connector 202 is provided with an annular first groove 203. The first blocking member 204 and the second blocking member 205 are provided on both sides of the first groove 203. A first inclined surface 207 is formed between the first groove 203, the first blocking member 204, and the second blocking member 205.
[0034] In some embodiments of this application, the first rotating head 206 is provided with threads, and the length of the first blocking member 204 is greater than that of the second blocking member 205.
[0035] Specifically, a threaded groove 305 is provided on one side of the connector 202. The strain rigid body 102 is connected to the connector 202 through the threaded groove 305. When the connector 202 is inserted into the locking mechanism, the first groove 203 on the connector 202 cooperates with the locking mechanism to achieve a locking effect. The first rotating head 206 achieves a second locking effect by rotating through the thread. When it is necessary to pull out the locking mechanism, only the connector 202 needs to be rotated. At this time, the first rotating head 206 disengages from the locking mechanism. Since the two sides of the first groove 203 are the first inclined surfaces 207, they will not prevent the connector 202 from disengaging.
[0036] Understandably, the first groove 203 cooperates with the locking mechanism, forming a radial mechanical interlock through the annular groove embedding into the locking mechanism. This restricts the lateral displacement and rotation of the connector 202, improving the connection's resistance to loosening under vibration. The first rotating head 206 is threaded and locked, with the tightened threads generating axial preload, filling the assembly gaps between components, enhancing the continuity of stress transmission, and reducing the risk of fretting wear.
[0037] The dual mechanism forms orthogonal directional constraints, strengthening the structural integrity of the measuring unit 101 and the strain unit. The first blocking member 204 is longer than the second blocking member 205. The longer blocking member bears the main tensile load, while the shorter blocking member provides auxiliary support. This differentiated design disperses stress concentration and extends the fatigue life of the connection mechanism. The inclined surface guides stress transmission. The inclined structure on both sides of the first groove 203 guides the load to spread smoothly along the axial direction, reducing the risk of local plastic deformation caused by stress abrupt changes at the root of the groove. The inclined surfaces on both sides of the first groove 203 form a self-unlocking ramp. During disassembly, rotating the connector 202 converts the constraint force of the locking mechanism into axial thrust, avoiding the rigid collision that occurs when the traditional slot structure is removed, and simplifying the disassembly process. It eliminates scratches on the groove edges during disassembly, maintaining the geometric accuracy for repeated use. The step-by-step operation logic first loosens the first rotating head 206 to release the axial preload, and then rotates to remove the radial slot. The two-stage separation mechanism avoids mechanical interference caused by synchronous operation and improves the fault tolerance of on-site operation. During reverse assembly, the groove can be blindly inserted and guided, and the inclined surface automatically corrects the positional deviation of the locking mechanism, eliminating the need for precision positioning tools.
[0038] In some embodiments of this application, the locking mechanism includes a first locking groove 301, a second locking groove 302, a locking bead 303, a second groove 304, and a threaded groove 305. The second locking groove 302 is fixedly connected to the measuring housing 1012. The first locking groove 301 is fixedly connected to the second locking groove 302. The diameter of the second locking groove 302 is smaller than that of the first locking groove 301, and a second inclined surface is formed between the second locking groove 302 and the first locking groove 301. A plurality of second grooves 304 are circumferentially formed on the first locking groove 301. Locking beads 303 are disposed in the second grooves 304. A threaded groove 305 is formed on the bottom wall of the second locking groove 302.
[0039] In some embodiments of this application, the size of the second groove 304 corresponds to the locking bead 303, and the size of the locking bead 303 corresponds to the first groove 203, and the size of the threaded groove 305 corresponds to the first rotating head 206.
[0040] Specifically, after the connector 202 is inserted, its first rotating head 206 enters the threaded groove 305 on the bottom wall of the second locking groove 302 via a thread. When the connector 202 is inserted, the locking ball 303 first contacts the second blocking member 205. At this time, the locking ball 303 retracts into the second recess 304. Then, as the connector 202 is continuously introduced, the locking ball 303 pops out and enters the first recess 203. At this time, the connector 202 is rotated to lock the first rotating head 206 in the threaded groove 305. The first blocking member 204 and the second blocking member 205 of the connector 202 respectively engage with the first locking groove 305. The inner walls of the first and second locking grooves 302 abut against each other to prevent the strain gauge 102 from shaking. When it is necessary to disassemble the connector 202, first rotate the connector 202 to rotate the first rotating head 206 out of the threaded groove 305. Since the locking ball 303 is spherical and the two sides of the first groove 203 are inclined, it will not affect the effect of pulling out the connector 202. Since the strain gauge 102 is connected to the connector 202 and the connector 202 is connected to the threaded groove 305, and the threaded groove 305 is directly connected to the strain gauge 1013, adding an extra connector 202 will not affect the monitoring data of the strain gauge 1013.
[0041] Understandably, the locking mechanism improves connection reliability under extreme vibration and variable load conditions through its adaptive radial locking and deep axial locking structure. During insertion, the locking ball 303 automatically retracts and springs into engagement after the first groove 203 is in place, forming a point-contact circumferential constraint. This, combined with the first rotating head 206 screwing into the deeply embedded threaded groove 305, generates a strong axial preload. Simultaneously, the first and second blocking members 204 and 205 abut against the groove wall to suppress bending moment transmission, jointly ensuring the structural integrity of the connection and fundamentally reducing the risk of misalignment. During disassembly, the threaded axial constraint is first released by rotation. During the outward pulling process, the inclined surface of the first groove 203 smoothly pushes the locking ball 303 back into the second groove 304. Spherical rolling friction replaces sliding friction, reducing disassembly resistance and protecting the contact surface. The graded unlocking logic avoids mechanical interference, and the semi-open structure of the second groove 304 helps to expel intruding foreign objects. The smaller diameter of the second locking groove 302 creates a cross-sectional change with the first locking groove 301. The stress flow transition and bending stiffness distribution are optimized through the second inclined surface. Multiple locking beads 303 distributed in a ring disperse the radial load and improve system redundancy. The precisely matched depth of the second groove 304 limits the displacement of the locking beads 303 and prevents the risk of dislodging. The hardening treatment of the key contact surface enhances the wear resistance and pressure resistance.
[0042] One convenient rebar gauge in the above embodiments separates the strain gauge core, allowing it to be welded to the rebar face separately and in advance. Because the strain gauge structure is relatively simple and lacks precision measuring elements, the heat and deformation generated during welding have a relatively small impact on its own axis, and the operator can focus more on ensuring precise alignment between the strain gauge and the rebar. After the strain gauge is firmly welded, the measuring part 101 is precisely assembled onto it via a connecting mechanism. This solves the problem of traditional rebar gauges having fixed, thickened strain gauge bodies at both ends, requiring integral butt welding to the rebar. The high temperature and thermal deformation generated during welding easily lead to uncontrollable micro-angular deviations between the sensor body and the rebar axis, resulting in misalignment. The precise threaded connection between the connecting mechanism (with a threaded groove 305 on one end) and the strain gauge (with a threaded protrusion on one end) inherently provides guidance and positioning functions. Finally, the connecting mechanism is secured by locking mechanisms at both ends of the measuring part 101, forming a rigid, multi-point constrained connection. This design effectively prevents any slight wobbling or displacement of the strain gauge during the final tightening process, ensuring that the axis of the measuring unit 101 is strictly coincident with the axis of the welded and fixed strain gauge. Therefore, it fundamentally reduces the risk of misalignment (non-coaxiality) between the measuring unit 101 and the overall reinforcing bar axis due to welding heat and installation disturbances, guaranteeing the authenticity of axial stress transmission and the accuracy of measurement data. The high temperature during welding is one of the main threats to precision sensors (such as vibrating wires and electronic components). While the high welding temperature only affects the individual strain gauge, the measuring unit 101, containing all precision measuring elements, is assembled at room temperature via a connecting mechanism after welding cooling. This isolates the direct and indirect (heat conduction) effects of welding heat on the core sensitive elements of the measuring unit 101, improving the initial measurement accuracy and long-term stability of the sensor and reducing the probability of early failure due to welding heat damage. The threaded connection itself possesses good tensile and compressive strength. The threaded engagement between the connecting mechanism and the strain unit, along with the final tightening of the connecting mechanism by the locking mechanism, together form a multi-layered mechanical locking structure. This enhances the connection stiffness and integrity of the entire sensor along the stress path of the reinforcing steel, reduces the risk of fretting wear, loosening, or even failure at the connection points during long-term service, especially under alternating or impact loads, and ensures the continuity and reliability of the stress transmission path.
[0043] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.
Claims
1. A convenient rebar gauge, characterized in that, include: The rebar gauge structure (1) includes a measuring part (101) and a strain unit. The strain unit is located at both ends of the measuring part (101). The strain unit is locked to the measuring part (101) through a connecting mechanism. Both ends of the measuring part (101) are provided with locking mechanisms. The connecting mechanism is fixedly connected to the strain unit. One end of the strain unit is provided with a threaded protrusion. One end of the connecting mechanism is provided with a threaded groove (305). The threaded protrusion corresponds to the threaded groove (305). The strain unit is threadedly connected to the connecting mechanism.
2. The easy-to-use rebar gauge according to claim 1, characterized in that, The measuring unit (101) includes an induction coil (1011), a measuring housing (1012), a strain gauge (1013), a thermometer (1014), and a connector (1015). The measuring housing (1012) is a hollow structure. The strain gauge (1013) is located inside the measuring housing (1012). The induction coil (1011) is located on one side of the middle of the strain gauge (1013). The thermometer (1014) is installed inside the measuring housing (1012). The induction coil (1011), the strain gauge (1013), and the thermometer (1014) are all electrically connected to the connector (1015).
3. The easy-to-use rebar gauge according to claim 2, characterized in that, The strain unit includes a strain rigid body (102), the diameter of which is larger than that of the rigid body to be measured, and the diameter of which corresponds to that of the connecting mechanism.
4. The easy-to-use rebar gauge according to claim 2, characterized in that, The connecting mechanism includes a connector (202), a first groove (203), a first blocking member (204), a second blocking member (205), and a first rotating head (206). One end of the connector (202) is provided with the threaded groove (305), and the end of the connector (202) away from the threaded groove (305) is provided with the first rotating head (206). The diameter of the connector (202) corresponds to the locking mechanism. The outer wall of the connector (202) is provided with an annular first groove (203). The first blocking member (204) and the second blocking member (205) are provided on both sides of the first groove (203). A first inclined surface (207) is formed between the first groove (203), the first blocking member (204), and the second blocking member (205).
5. The easy-to-use rebar gauge according to claim 4, characterized in that, The first rotating head (206) has a thread, and the length of the first blocking member (204) is greater than that of the second blocking member (205).
6. The easy-to-use rebar gauge according to claim 5, characterized in that, The locking mechanism includes a first locking groove (301), a second locking groove (302), a locking bead (303), a second groove (304), and a threaded groove (305). The second locking groove (302) is fixedly connected to the measuring housing (1012). The first locking groove (301) is fixedly connected to the second locking groove (302). The diameter of the second locking groove (302) is smaller than that of the first locking groove (301), and a second inclined surface is formed between the second locking groove (302) and the first locking groove (301). A plurality of second grooves (304) are circumferentially formed on the first locking groove (301). A locking bead (303) is provided in the second groove (304). A threaded groove (305) is formed on the bottom wall of the second locking groove (302).
7. The easy-to-use rebar gauge according to claim 6, characterized in that, The size of the second groove (304) corresponds to the locking bead (303), and the size of the locking bead (303) corresponds to the first groove (203), and the size of the threaded groove (305) corresponds to the first rotating head (206).