Universal self-locking and self-adapting quick connector for reinforcing steel bars

Abstract

The invention relates to the technical field of steel bar connection in constructional engineering, and particularly discloses a universal self-locking and self-adapting quick connector for steel bars, which comprises a connecting steel bar body and a slot connecting steel bar body, and further comprises a plug assembly for forming a stable support stress structure for the connecting steel bar body and the slot connecting steel bar body; according to the dynamic self-locking mechanism, the design of the cylindrical surface at the bottom of the inserting rod in the prior art is improved, the defect that in the original design, the requirements for anchor piece materials and hardness are high is overcome, dependence on the anchor piece material performance is reduced, more types of materials can be selected for manufacturing anchor pieces under the condition that the same connecting performance requirement is met, and the cost is reduced. Compared with the prior art, the anchor piece has the advantages that the material selection range is widened, the production cost is reduced, meanwhile, the design of three separated anchor pieces in the prior art is improved into the design of a collet-type integral eight-piece anchor piece, and the defects that the original anchor piece is high in machining precision requirement, inconvenient to install, easy to cause stress concentration and the like are overcome.

Description

Technical Field

[0001] This invention belongs to the field of steel bar connection technology in building engineering, and specifically relates to a universal self-locking adaptive quick connector for steel bars. Background Technology

[0002] Solving the problem of rebar connection is key to solving the overall integrity of prefabricated structures. On the basis of ensuring excellent connection performance of the joints, researching more reasonable joint structures and sleeve production processes can reduce the cost of rebar connection joints, increase construction speed, and have important significance for the promotion of building industrialization.

[0003] A search revealed a patent application with publication number CN113684972B, which discloses a rebar self-locking connector and a self-locking connection method. The connector includes a lock cylinder, a lock barrel, and locking pin units. The lock cylinder comprises a first rebar connection section and a lock barrel connection section. The lock barrel connection section has several locking pin holes, each engaging with a locking pin unit. Each locking pin unit includes a locking pin that can move back and forth along the locking pin hole. The lock barrel comprises a second rebar connection section and a lock cylinder connection section. The lock cylinder connection section is a hollow structure with its end face away from the lock barrel open. Several locking teeth are arranged along the length of the lock cylinder connection section on its inner wall. The gap between adjacent locking teeth engages with the corresponding locking pin to form a self-locking state. This invention eliminates the need for pre-reserved anchorage lengths for the rebar and does not rely on grout for bonding and anchoring, facilitating the installation of precast concrete components. Furthermore, the mechanical connection method avoids the aging and failure problems of chemical grouting connections, improving the reliability of the rebar connection.

[0004] Compared to the aforementioned documents, while they do not require pre-reserved anchorage lengths for reinforcing bars and do not rely on grouting for bonding and anchoring, facilitating the installation of precast concrete components, and employ mechanical connection methods to avoid the aging and failure issues of chemical grouting connections, thus improving the reliability of reinforcing bar connections, current reinforcing bar connections mainly rely on threaded sleeves or grouting sleeves: the former requires rotational force application, making it unsuitable for fixing reinforcing bars in precast components; the latter relies on grouting bonding, presenting challenges such as complex construction processes, unreliable grouting quality, difficult testing, and long construction periods. In modular buildings, reinforcing bars are prefabricated into reinforcing cages or components, and traditional methods cannot meet the requirements for rapid connection. While existing self-locking sleeves simplify operation, they suffer from insufficient locking force, sensitivity to reinforcing bar position deviations, and easy slippage. Therefore, a universal self-locking adaptive quick connector for reinforcing bars is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a universal self-locking adaptive quick connector for reinforcing bars, so as to solve the problems of traditional mechanical and sleeve grouting connections that require manual tightening, have poor adaptability, low construction efficiency, and high overall cost.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A universal self-locking adaptive quick connector for reinforcing bars includes a connecting body for the reinforcing bar and a slot for connecting the reinforcing bar, and further includes:

[0008] A plug assembly is used to form a stable supporting structure for the connecting steel bar body and the slot connecting steel bar body;

[0009] The slot assembly is used to ensure the stability and reliability of axial force transmission in the connector.

[0010] Preferably, the plug assembly includes a connecting rebar body, a plug sealing gasket, a spherical plug, a plug support nut, and a plug connecting sleeve. Both sides of the plug connecting sleeve are provided with first threads. One end of the plug connecting sleeve is connected to the connecting rebar body via the first thread, and the other end of the plug connecting sleeve is connected to the plug support nut via the first thread. Through this threaded connection method, the various components are tightly integrated to form a plug force-bearing system. This system ensures that when the rebar is under load, the force can be effectively transmitted and distributed among the threaded connecting rebar body, the plug connecting sleeve, the plug support nut, and the spherical plug, thereby ensuring the stability and reliability of the plug assembly during operation. Simultaneously, the plug sealing gasket provides a sealing function, preventing external impurities from entering the plug assembly, further improving the durability and service life of the entire assembly.

[0011] Preferably, one end of the spherical plug is spherically shaped, and the plug support nut has a spherical groove. The spherical part of the spherical plug and the spherical groove of the plug support nut are interlocked to form a stable support structure. This unique design gives the plug good axial angle adaptability, allowing axial angle deflection within a range of ±2.5°. This angle deflection capability can effectively compensate for the deviation of the reinforcing bar axis that may occur during actual installation, reducing the stringent requirements for installation accuracy and enhancing the applicability and fault tolerance of the connector under different working conditions.

[0012] Preferably, the slot assembly includes an anchor ring support nut, an anchor ring body, a collet-type anchor plate, a spring upper washer, a spring body, a spring positioning washer, a slot rebar connecting nut, and a slot connecting sleeve. The plug connecting sleeve has slots on both sides of its bottom. Each slot has a second thread at both ends. One end of the slot is connected to the anchor ring support nut via the second thread, and the other end of the slot is connected to the slot rebar connecting nut via the second thread. The anchor ring body is supported and connected to the lower end of the anchor ring support nut, forming a horizontally sliding force-bearing end face. This sliding range is allowed within ±2mm. This design effectively compensates for installation errors and positional deviations within a certain range, enhancing the connector's adaptability.

[0013] Preferably, the collet-type anchor plate is placed inside the anchor ring body, and the outer conical surface of the collet-type anchor plate is tightly fitted with the inner conical surface of the anchor ring body. When axial tension is generated between the spherical insert and the collet-type anchor plate, this tightly fitted conical structure can withstand the friction, compression and axial tension between the outer conical surface of the spherical insert and the inner conical surface of the collet-type anchor plate, thereby achieving effective force transmission and bearing.

[0014] Preferably, the spring washer is fitted onto the lower end face of the collet-type anchor plate, forming a three-level elastic support system with the spring body and the spring positioning washer, which together anchor to the upper end face of the slot rebar connecting nut. This spring telescopic structure design has important functions. On the one hand, it can automatically and accurately push the collet-type anchor plate to the actual force-bearing anchoring and locking position of the plug rod under the telescopic function of the spring body when axial position deviation occurs under complex working conditions such as rebar axial positioning (allowing ±5mm), ensuring the stability and reliability of the axial force transmission of the connector. On the other hand, it can provide pre-tightening force to the contact cone surfaces of the spherical plug rod, collet-type anchor plate, and anchor ring body. By applying appropriate pre-tightening force, the contact area percentage of each cone surface can be guaranteed to meet the design requirements, thereby improving the connection performance and reliability of the connector.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] The dynamic self-locking mechanism implemented in this invention improves upon the design of the cylindrical bottom surface of the insertion rod in the prior art by changing it to a conical surface. This improvement solves the defect of the original design that requires high material and hardness of the anchor plate, reduces the dependence on the performance of the anchor plate material, and allows for the selection of more types of materials to make the anchor plate while meeting the same connection performance requirements, thus broadening the range of material choices and helping to reduce production costs. At the same time, it improves the existing 3-piece separate anchor plate design into a collet-type integral 8-piece anchor plate design. This improvement solves the defects of the original anchor plate, such as high processing precision requirements, inconvenience in installation, and easy stress concentration.

[0017] This invention employs a universal mechanical quick connection method for prestressed hollow roof trusses, eliminating the need for rotation and grouting. The connection time for a single node is reduced to within 5 seconds, improving efficiency by more than 10 times compared to traditional sleeve grouting. Standard components automatically compensate for deviations of ±5mm in the axial direction, ±2.5° in the axial angle, and ±2mm in the horizontal direction. Custom production with automatic compensation for any axial deviation is available upon design. The dynamic wedging mechanism ensures pull-out resistance exceeding 1.1 times the strength of the reinforcing steel base material, surpassing the requirements of the industry standard JGJ107-2016 Class I joints. The elimination of grouting reduces pollution and lowers overall costs by 20%–40%. Attached Figure Description

[0018] Figure 1 This is a structural diagram of the present invention;

[0019] Figure 2 This is a cross-sectional view of the present invention;

[0020] Figure 3 This is a connection structure diagram of the spherical plug of the present invention;

[0021] Figure 4 This is a fatigue life cycle analysis diagram of the present invention;

[0022] Figure 5 This is the tensile strength test report and high stress test data diagram of the present invention.

[0023] In the diagram: 1. Connecting rebar body; 2. Plug sealing gasket; 3. Spherical insert; 4. Insert support nut; 5. Plug connecting sleeve; 6. Anchor ring support nut; 7. Anchor ring body; 8. Clip-type anchor plate; 9. Spring upper washer; 10. Spring body; 11. Spring positioning washer; 12. Slot rebar connecting nut; 13. Slot connecting sleeve; 14. Slot connecting rebar. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] like Figure 1-3As shown, a universal self-locking adaptive quick connector for reinforcing bars includes a connecting reinforcing bar body 1 and a slot connecting reinforcing bar body 14, and also includes a plug assembly for forming a stable support structure for the connecting reinforcing bar body 1 and the slot connecting reinforcing bar body 14. The plug assembly includes the connecting reinforcing bar body 1, a plug sealing gasket 2, a ball-shaped plug rod 3, a plug rod support nut 4, and a plug connecting sleeve 5. Both sides of the plug connecting sleeve 5 are provided with first threads. One end of the plug connecting sleeve 5 is connected to the connecting reinforcing bar body 1 through the first thread, and the other end of the plug connecting sleeve 5 is connected to the plug rod support nut 4 through the first thread. Through this threaded connection method, the various components are tightly combined to form a plug force-bearing system. This system can ensure that when the reinforcing bar is under load, the force can be effectively transmitted and distributed among the threaded connecting reinforcing bar body 1, the plug connecting sleeve 5, the plug rod support nut 4, and the ball-shaped plug rod 3, thereby ensuring the stability and reliability of the plug assembly during operation. At the same time, the plug sealing gasket 2 can play a sealing role to prevent external impurities from entering the interior of the plug assembly, further improving the durability and service life of the entire assembly.

[0026] The present invention is further described in detail. One end of the spherical plug 3 is spherical, and the plug support nut 4 is provided with a spherical groove. The spherical part of the spherical plug 3 and the spherical groove of the plug support nut 4 are interlocked to form a stable support structure. This unique design gives the plug good axial angle adaptability, allowing axial angle deflection within a range of ±2.5°. This angle deflection capability can effectively compensate for the deviation of the steel bar axis that may occur during actual installation, reduce the stringent requirements for installation accuracy, and enhance the applicability and fault tolerance of the connector under different working conditions.

[0027] like Figure 1-3 As shown, the slot assembly is used to ensure the stability and reliability of the axial force transmission of the connector. The slot assembly includes an anchor ring support nut 6, an anchor ring body 7, a collet-type anchor plate 8, a spring upper washer 9, a spring body 10, a spring positioning washer 11, a slot rebar connecting nut 12, and a slot connecting sleeve 13. Slots are provided on both sides of the bottom of the plug connecting sleeve 5. A second thread is provided at both ends of the slot. One end of the slot is connected to the anchor ring support nut 6 through the second thread, and the other end of the slot is connected to the slot rebar connecting nut 12 through the second thread. The anchor ring body 7 is supported and connected to the lower end of the anchor ring support nut 6, which can form a horizontally sliding force-bearing end face. The sliding range is allowed to be within ±2mm. This design can effectively compensate for installation errors and position deviations within a certain range and enhance the adaptability of the connector.

[0028] The present invention is further described in detail. The collet-type anchor plate 8 is placed inside the anchor ring body 7. The outer conical surface of the collet-type anchor plate 8 is tightly fitted with the inner conical surface of the anchor ring body 7. When an axial tensile force is generated between the spherical insert rod 3 and the collet-type anchor plate 8, this tightly fitted conical surface structure can withstand the friction, compression and axial tensile force between the outer conical surface of the spherical insert rod 3 and the inner conical surface of the collet-type anchor plate 8, thereby realizing the effective transmission and bearing of force.

[0029] The invention is further described in detail below. The spring upper washer 9 is fitted to the lower end face of the collet-type anchor plate 8, and together with the spring body 10 and the spring positioning washer 11, they form a three-level elastic support system, which is anchored to the upper end face of the slot rebar connecting nut 12. This spring telescopic structure design has important functions. On the one hand, when axial position deviation occurs under complex working conditions such as rebar axial positioning (allowing ±5mm), the telescopic function of the spring body 10 can automatically and accurately push the collet-type anchor plate 8 to the actual force-bearing anchoring and locking position of the plug rod, ensuring the stability and reliability of the axial force transmission of the connector. On the other hand, it can provide pre-tightening force to the contact cone surfaces of the spherical plug rod 3, the collet-type anchor plate 8 and the anchor ring body 7. By applying appropriate pre-tightening force, the contact area percentage of each cone surface can be guaranteed to meet the design requirements, thereby improving the connection performance and reliability of the connector.

[0030] As can be seen from the above, by utilizing the spring upper washer 9 to fit against the lower end face of the collet-type anchor plate 8, together with the spring body 10 and the spring positioning washer 11, a three-level elastic support system is formed, which together anchors to the upper end face of the slot steel bar connecting nut 12. This structure allows ±5mm axial displacement through the spring stroke compensation mechanism, realizing two core functions:

[0031] 1. Dynamic position locking: When the axial positioning deviation of the reinforcing bar is ±5mm, the horizontal positioning deviation is ±2mm, and the axial deviation angle of the reinforcing bar is ±2.5°, the compressible stroke design compression amount of the spring body 10 is 25mm, which drives the collet anchor plate 8 to slide linearly along the outer conical surface of the spherical plug rod 3. Through the spring reaction force, the anchor plate is automatically wedged to the actual force anchoring position of the spherical plug rod 3, the anchor ring body 7, and the anchor ring support nut 6. Finite element analysis verifies that the connector can still maintain ≥92% of the design contact area under the above deviation conditions, avoiding force transmission interruption and stress concentration caused by position deviation.

[0032] II. Conical Pre-tightening Reinforcement: Taking a 20mm steel bar connector as an example, a 60Si2MnA rectangular spring with a stiffness of 39.2-95.7 N / mm provides an initial pre-tightening force of 352N-1339N. The pre-stress is uniformly transferred to the lower end face of the collet-type anchor plate 8 through the upper washer 9 of the rectangular spring. This pre-tightening force is converted into a contact stress of 35-50MPa through the outer conical surface of the anchor plate, ensuring that the actual contact area between the outer conical surface Ra0.8μm of the spherical plug 3 and the inner conical surface of the anchor plate is ≥85%. According to the GB / T1804-m tolerance standard, this is 41% higher than the contact area ≤60% of the traditional non-pre-tightening structure, effectively suppressing the risk of conical surface slippage failure.

[0033] The working principle achieved by the above technical solution is as follows: When the spherical insert 3 is inserted, its front inclined surface interacts with the collet anchor plate 8, pushing the collet anchor plate 8 to move downward. As the collet anchor plate 8 moves downward, its upper opening opens continuously. When the opening of the collet anchor plate 8 is larger than the diameter of the lower cone of the spherical insert 3, under the reaction force of the rectangular spring body 10, the collet anchor plate 8 moves upward rapidly, anchors into the anchor ring, and self-locks in the cone-shaped force-bearing position of the spherical insert 3. When the steel bar is under tension, the cone surfaces between the spherical insert 3 and the collet anchor plate 8, and between the collet anchor plate 8 and the anchor ring, will generate axial component force. This axial component force pushes the collet anchor plate 8 to wedge tighter, thus forming a self-anchoring effect of "tightening as it is pulled".

[0034] By setting the above technical solution, this dynamic self-locking mechanism improves the design of the cylindrical surface at the bottom of the insertion rod in the prior art by changing it to a conical surface. This improvement solves the defect of high requirements for anchor material and hardness in the original design, reduces the dependence on the performance of anchor material, and allows more types of materials to be used to make anchors while meeting the same connection performance requirements, thus broadening the range of material selection and helping to reduce production costs.

[0035] Simultaneously, the existing three-piece separate anchor plate design was improved into a clamp-type integral eight-piece anchor plate design. This improvement solves the defects of the original anchor plate, such as high processing precision requirements, inconvenient installation, and easy stress concentration. Taking a 20mm diameter threaded steel bar mechanical self-locking adaptive quick connector as an example, according to the requirements of JGJ107 "Technical Specification for Mechanical Connection of Steel Bars", the fatigue life cycle of the connector under stress at 0.575 times the yield strength of the steel bar (230 MPa) is simulated and analyzed. Figure 4 Theoretical analysis shows that the fatigue life reaches over 7.1 million cycles, far exceeding the standard fatigue life requirement of 2 million cycles. All other indicators meet the design requirements for 20mm threaded steel connection performance. The actual ultimate tensile strength test report and high-stress test data are available in [link to relevant documentation]. Figure 5 ;

[0036] The installation and construction process of this invention is as follows:

[0037] Prefabrication stage: Connect the plug connecting sleeve (5) and the slot connecting sleeve (13) to the reinforcing steel of the prefabricated component by thread (torque control 30-50 N·m). The front end of the sleeve is flush with the surface of the component. See Figure 3 As shown;

[0038] On-site installation: Check the sleeve for debris and clean it thoroughly. First, install the slot plug accessories in the following order: spring positioning washer 11 - spring body 10 - spring upper washer 9 - collet anchor plate 8 - anchor ring body 7 - tighten the anchor ring support nut 6 with an electric wrench. After the slot accessories are installed, install the ball-shaped insert 3 into the insert support nut 4 - install the plug sealing washer 2, and tighten the support nut of the ball-shaped insert 3 into the plug connecting sleeve 5 with an electric wrench. After the plug accessories are installed, immediately spray the prepared high-strength, corrosion-resistant, and high-ductility interface agent onto the end face of the component. After even spraying, quickly insert the ball-shaped insert 3 of the component with the plug installed into the hole of the slot anchor ring support nut 6 of the component with the slot accessories installed. The vertical component uses its own weight, and the horizontal component uses external force to achieve the connection and installation of the component joint reinforcement. The insertion process takes less than 5 seconds, realizing the component can be used immediately after insertion. This is 10 times more efficient than the traditional grouting sleeve process of 50 seconds / node.

[0039] In summary, this invention utilizes a universal mechanical quick connection method for prestressed hollow roof trusses, eliminating the need for rotation and grouting. The connection time for a single node is reduced to within 5 seconds, improving efficiency by more than 10 times compared to traditional sleeve grouting. Standard components automatically compensate for deviations of ±5mm in the axial direction, ±2.5° in the axial angle, and ±2mm in the horizontal direction. Custom production with automatic compensation for any deviation in the axial direction is available based on the design. The dynamic wedging mechanism ensures pull-out resistance exceeding 1.1 times the strength of the reinforcing bar, surpassing the requirements of the industry standard JGJ107-2016 Class I joints. The elimination of grouting reduces pollution and lowers overall costs by 20%–40%.

[0040] The prestressed hollow roof truss beam using the universal mechanical self-locking adaptive fast connection technology for steel bars has a direct cost reduction of (1-30820 / 38902)*100%=20.8% compared to the traditional precast roof truss beam. The crack resistance is improved by 2.3 times, the bending resistance by 1.13 times, and the shear resistance by 1.05 times. It can be seen that the universal mechanical fast self-locking adaptive fast connector for steel bars is a powerful tool for improving the quality and efficiency of building industrialization.

[0041] Furthermore, this design application is applied to the rapid adaptive self-locking connection of general-purpose reinforcing bars. This dynamic self-locking mechanism improves the design of the cylindrical surface at the bottom of the insertion rod in the prior art by changing it to a conical surface. This improvement solves the defect of the original design that requires high material and hardness of the anchor plate, reduces the dependence on the performance of the anchor plate material, and allows more types of materials to be used to make the anchor plate while meeting the same connection performance requirements, thus broadening the range of material selection and helping to reduce production costs. At the same time, it improves the existing 3 separate anchor plate design to a collet-type integral 8-piece anchor plate design. This improvement solves the defects of the original anchor plate, such as high processing accuracy requirements, inconvenience in installation, and easy stress concentration.

[0042] Although embodiments of the 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 invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A universal self-locking adaptive quick connector for reinforcing bars, characterized in that, Including the connecting steel bar body (1) and the slot connecting steel bar body (14), and also including: The plug assembly is used to form a stable supporting structure for the connecting steel bar body (1) and the slot connecting steel bar body (14); The slot assembly is used to ensure the stability and reliability of axial force transmission in the connector.

2. The universal self-locking adaptive quick connector for reinforcing bars according to claim 1, characterized in that: The plug assembly includes a connecting steel bar body (1), a plug sealing gasket (2), a spherical plug rod (3), a plug rod support nut (4), and a plug connecting sleeve (5). Both sides of the plug connecting sleeve (5) are provided with first threads. One end of the plug connecting sleeve (5) is connected to the connecting steel bar body (1) through the first thread, and the other end of the plug connecting sleeve (5) is connected to the plug rod support nut (4) through the first thread.

3. The universal self-locking adaptive quick connector for reinforcing bars according to claim 2, characterized in that: One end of the spherical insert (3) is spherical, and the insert support nut (4) is provided with a spherical groove. The spherical part of the spherical insert (3) and the spherical groove of the insert support nut (4) are fitted together.

4. The universal self-locking adaptive quick connector for reinforcing bars according to claim 2, characterized in that: The slot assembly includes an anchor ring support nut (6), an anchor ring body (7), a collet anchor plate (8), a spring upper washer (9), a spring body (10), a spring positioning washer (11), a slot rebar connecting nut (12), and a slot connecting sleeve (13). The plug connecting sleeve (5) has slots on both sides of its bottom. Both ends of the slots have second threads. One end of the slot is connected to the anchor ring support nut (6) through the second thread, and the other end of the slot is connected to the slot rebar connecting nut (12) through the second thread. The anchor ring body (7) is supported and connected to the lower end of the anchor ring support nut (6).

5. A universal self-locking adaptive quick connector for reinforcing bars according to claim 4, characterized in that: The collet-type anchor plate (8) is placed inside the anchor ring body (7), and the outer conical surface of the collet-type anchor plate (8) is closely fitted with the inner conical surface of the anchor ring body (7).

6. A universal self-locking adaptive quick connector for reinforcing bars according to claim 4, characterized in that: The upper spring washer (9) is fitted to the lower end face of the collet anchor plate (8) and forms a three-level elastic support system with the spring body (10) and the spring positioning washer (11), which are anchored together to the upper end face of the slot steel bar connecting nut (12).

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