Connection structure of leakage protection module

Abstract

The utility model provides a connection structure of leakage protection module, including contact mechanism and mutual inductor, the mutual inductor center is worn with the copper bar of connection, the copper bar of connection extends to the inside of contact mechanism, the contact mechanism is provided with fixed hole towards the copper bar of connection direction, the fixed hole is fixed with fixed copper bar, the upper end surface of fixed copper bar is in line with the copper bar of connection, the lower end surface of fixed copper bar is fixed with fastening sleeve, the corresponding position of fastening sleeve, fixed copper bar and copper bar of connection is provided with fastening hole and only attacks the tooth in fastening hole on fastening sleeve. The utility model has the advantages of: through only the fastening hole on fastening sleeve is attacked tooth processing, avoided the cost increase and mechanical strength weakened problem caused by directly attacking tooth to soft copper material, reduced the additional mechanical processing steps such as drilling and thread cutting, thereby reduce material waste and improve production efficiency.

Description

TECHNICAL FIELD

[0001] The utility model relates to a connecting structure in circuit breaker, especially a connecting structure of leakage protection module. BACKGROUND

[0002] In the circuit breaker system, the connection between the contact mechanism and the transformer is usually achieved by copper bars. This structure is widely used in power distribution, industrial control and protection circuits to ensure reliable transmission and measurement of current. In specific use, the copper bars are designed to match the shape of the contact mechanism and the transformer interface. During installation, the operator first positions the copper bar at the connection point, and then uses screws or bolts to fix it through the threaded holes previously processed on the copper bar. This connection method can transmit high current and withstand electromagnetic force and thermal expansion during normal operation of the circuit breaker, ensuring good electrical contact, reducing contact resistance and energy loss, and thus ensuring stable operation of the circuit and fault protection function. This structure is commonly used in low-voltage and medium-voltage circuit breakers, and is applied in substations, distribution panels and industrial equipment, requiring firm connection to withstand frequent operation and harsh environments.

[0003] However, there are some defects in the prior art, mainly due to the tapping treatment of the copper bars used for connection. First, the tapping process increases the manufacturing cost and time, as it requires additional machining steps such as drilling and thread cutting, which not only rely on specialized equipment, but also may cause material waste and reduce production efficiency. Second, tapping weakens the mechanical strength of the copper bar, especially when the copper bar itself is softer than other metals, forming a stress concentration point in the threaded area, which is prone to fatigue cracks or thread damage in long-term high-load or vibration environments, affecting the reliability and safety of the connection, and even causing circuit failure. These defects limit the applicability of this structure in high-voltage or high-reliability applications. SUMMARY

[0004] To solve the problem of high cost and weak strength of copper bar tapping in the prior art, the utility model provides a connecting structure of leakage protection module.

[0005] To achieve the above purpose, the utility model technical scheme is as follows: a connecting structure of leakage protection module, comprising a contact mechanism and a transformer, a connecting copper bar is provided at the center of the transformer, the connecting copper bar extends to the inside of the contact mechanism, a fixed hole is provided on the contact mechanism facing the direction of the connecting copper bar, a fixed copper bar is fixed in the fixed hole, the upper end surface of the fixed copper bar is in close contact with the connecting copper bar, a fastening sleeve is fixed to the lower end surface of the fixed copper bar, corresponding positions of the fastening sleeve, the fixed copper bar and the connecting copper bar are provided with fastening holes, and only the fastening holes on the fastening sleeve are tapped.

[0006] The beneficial effects of this invention are as follows: By tapping only the fastening holes on the fastening sleeve, the increased cost and weakened mechanical strength caused by directly tapping soft copper material are avoided. Additional machining steps such as drilling and thread cutting are reduced, thereby reducing material waste and improving production efficiency. Simultaneously, the overlapping structure of the two copper busbars enhances the overall connection strength, disperses stress concentration points, and improves reliability and safety under high pressure or high load environments, reducing the risk of fatigue cracks or open circuit failures. As a preferred embodiment, the fastening sleeve can be cylindrical or rectangular with threaded grooves on its inner wall. It is fixed to the lower end face of the fixed copper busbar by press-fitting or welding, ensuring that the fastener only mates with the threaded holes of the fastening sleeve, while the corresponding holes of the connecting and fixed copper busbars remain smooth. During assembly, the fastener is screwed into the threaded holes of the fastening sleeve, applying pressure to ensure a tight fit between the copper busbars, preventing deformation or damage to the copper material caused by tapping. As another preferred approach, the overlapping surfaces of the fixed copper busbar and the connecting copper busbar can be designed to be rough or have a slightly raised texture to increase the contact area and the coefficient of friction. When the fasteners are tightened, the surface interlocking effect enhances the connection stability and prevents loosening under vibration. At the same time, the overlapping structure of the copper busbar improves the overall mechanical strength by uniformly distributing the load.

[0007] Furthermore, the fastening sleeve is made of iron.

[0008] Iron fastening sleeves offer higher mechanical strength and wear resistance, making them more suitable than copper for bearing the thread tightening force of fasteners. This reduces thread wear or deformation caused by long-term use, thereby extending the service life of the connection structure and ensuring connection reliability. Iron also exhibits good fatigue resistance, remaining stable under vibration or high load conditions and preventing connection failure due to material softening. As a preferred option, the fastening sleeve can be made of low-carbon steel or alloy steel, with its surface heat-treated (e.g., quenching or carburizing) to enhance hardness and corrosion resistance. It is formed into a sleeve structure with internal threads through stamping or machining. During assembly, it is fixed to the copper busbar by welding or press fitting, ensuring that the iron sleeve bears the main stress when the fastener is screwed in, while the copper busbar only serves as a conductive and support component, avoiding the direct tapping defects of copper. As another preferred approach, the iron fastening sleeve can be designed as a multi-layer composite structure, for example, with an outer anti-rust coating and an inner high-strength steel core, which is connected to the fixed copper busbar by bolts or rivets. In this way, the iron component undertakes the mechanical locking function during the fastening process, while the copper busbar maintains its original conductivity. The overall structure optimizes cost and production efficiency while ensuring strength.

[0009] Furthermore, the fastening sleeve has a protruding part on the end face facing away from the fixed copper busbar, the protruding part is spliced ​​with the fastening hole and the protruding part is tapped.

[0010] This structure increases the connection depth of the fastener through the protrusion, resulting in a more secure thread lock, reducing the risk of loosening, dispersing stress concentration, and improving stability under vibration or high-load environments. The protrusion design also allows for longer thread engagement, enhancing tensile strength and shear resistance, and preventing premature failure due to insufficient connection depth. As a preferred approach, the protrusion can be designed as a cylindrical or conical projection, its height adjusted according to the fastener length. It is integrally formed on the end face of the fastening sleeve through machining. The protrusion has threaded holes aligned with the fastening holes. During assembly, the fastener is screwed into the threaded portion of the protrusion, extending into the corresponding holes of the fixing and connecting copper busbars. This increases the thread contact length, improving the locking effect, while the protrusion acts as a stress buffer, reducing direct impact on the copper busbars. As another preferred approach, the protrusion can be designed as a multi-segment structure, for example, the base is welded to or threaded to the fastening sleeve, and the top is provided with a guide bevel to facilitate the insertion of the fastener. Its internal threads are designed with fine or coarse threads to adapt to different load requirements. During the fastening process, the protrusion bears the main locking force and transmits it to the copper busbar through its rigidity, avoiding local deformation of the copper material, thereby ensuring the long-term reliability of the connection.

[0011] Furthermore, it also includes a fastener that mates with a fastening hole. The fastener includes a head and a bolt. The outer surface of the bolt is provided with threads. The head abuts against the end face of the connecting copper busbar that is opposite to the fixed copper busbar.

[0012] This fastener, through its head and plug design, ensures uniform clamping force, prevents relative displacement between copper busbars, and improves the stability of electrical contact and the robustness of mechanical connection. The threaded plug engages with the tapped hole of the fastening sleeve for reliable locking, while the head distributes pressure to avoid localized overload and reduce the risk of copper busbar deformation. As a preferred option, the fastener can use a standard bolt or screw structure with a hexagonal or round head with a washer. The plug thread uses a self-locking or anti-loosening thread. During assembly, the head presses against the outer surface of the connecting copper busbar, and the plug passes through the holes of the copper busbar and the fixing copper busbar before being screwed into the threaded hole of the fastening sleeve. Torque control ensures uniform clamping force, while the head washer distributes pressure to prevent damage to the copper busbar surface. Alternatively, the fastener can be designed as a double-ended bolt structure, with one end threaded into the fastening sleeve and the other end locked to the connecting copper busbar side by a nut. This bidirectional locking enhances stability under high pressure. The head or nut surface of the fastener has an insulating or conductive coating at the contact point with the copper busbar to optimize electrical performance. The overall structure achieves a highly reliable connection through mechanical locking and pressure distribution.

[0013] Furthermore, there are two fastening holes, which are respectively located at the center of the connecting copper busbar, the fixed copper busbar, and the fastening sleeve. The corresponding end faces of the fixed copper busbar and the fastening sleeve are respectively provided with matching limiting posts and limiting holes. The limiting posts and limiting holes are respectively arranged opposite to each other on both sides of the fixed copper busbar and the fastening sleeve.

[0014] The opposing arrangement of the two fastening holes and the limiting structure enhances the alignment accuracy and torsional resistance of the components, preventing misalignment or rotation during assembly or use, and improving the stability and consistency of the connection. The cooperation between the limiting posts and the limiting holes also simplifies the installation process, reduces reliance on additional fixtures, and improves production efficiency. As a preferred approach, the limiting posts can be designed as cylindrical or prismatic protrusions, and the limiting holes are correspondingly shaped blind or through holes, formed by stamping or machining on the end faces of the fixing copper busbar and the fastening sleeve. The opposing arrangement means they are set along a diagonal direction. During assembly, the limiting posts are inserted into the limiting holes for initial positioning, ensuring alignment of the fastening holes, and then locked in place with fasteners. This mechanical interlocking prevents relative movement of the components. As another preferred approach, the limiting structure can be designed as multiple sets of opposing arrangements. For example, limiting posts and holes can be set at the four corners of the fixed copper busbar and the fastening sleeve. The anti-torsion performance is enhanced by the staggered arrangement. The surface of the limiting post can be chamfered or tapered to facilitate insertion. During the fastening process, the limiting structure bears part of the shear force, reducing the dependence on fasteners, thereby optimizing the durability and ease of installation of the overall structure. Attached Figure Description

[0015] Figure 1 This is a perspective view of an embodiment of the present utility model; Figure 2 This is a cross-sectional view of the fastening hole in an embodiment of the present invention; Figure 3 This is a disassembly diagram of an embodiment of the present utility model; Figure 4 This is a partial enlarged view of the connection between the contact mechanism and the connecting copper busbar in an embodiment of this utility model. Detailed Implementation

[0016] The connection structure of a leakage current protection module according to an embodiment of this utility model is as follows: Figures 1-4The diagram shows a contact mechanism 11 and a current transformer 12. A connecting copper busbar 13 passes through the center of the current transformer 12 and extends into the contact mechanism 11 to achieve electrical connection. The contact mechanism 11 has a fixing hole (not shown) facing the connecting copper busbar 13. A fixing copper busbar 15 is fixedly installed in the fixing hole (not shown). The upper end face of the fixing copper busbar 15 fits against the connecting copper busbar 13 to form a stacked structure, thereby enhancing connection strength and conductivity. A fastening sleeve 16 is fixedly connected to the lower end face of the fixing copper busbar 15. The fastening sleeve 16 is made of iron to provide higher mechanical strength and durability. Fastening holes 17 are provided at corresponding positions on the fastening sleeve 16, the fixing copper busbar 15, and the connecting copper busbar 13. Tapping is only performed on the fastening holes 17 located on the fastening sleeve 16 to avoid burrs or deformation caused by directly tapping the soft copper material. The stacking of the two copper busbars further enhances the overall connection stability.

[0017] The fastening sleeve 16 has a protruding part 18 on the end face facing away from the fixed copper busbar 15. The protruding part 18 is spliced ​​with the fastening hole 17 and the protruding part 18 is tapped to increase the connection depth and tensile strength of the fastener. It also includes a fastener 19 that mates with the fastening hole 17. The fastener 19 includes a head 191 and a bolt 192. The outer surface of the bolt 192 is provided with threads. The head 191 abuts against the end face of the connecting copper busbar 13 facing away from the fixed copper busbar 15. By tightening the fastener 19, the connecting copper busbar 13, the fixed copper busbar 15 and the fastening sleeve 16 can be pressed and fixed. There are two fastening holes 17, which are respectively located at the center of the connecting copper busbar 13, the fixed copper busbar 15 and the fastening sleeve 16. The corresponding end faces of the fixed copper busbar 15 and the fastening sleeve 16 are respectively provided with matching limiting posts 110 and limiting holes 111. The limiting posts 110 and limiting holes 111 are respectively arranged opposite to each other on both sides of the fixed copper busbar 15 and the fastening sleeve 16, that is, arranged along the diagonal direction, so as to achieve accurate positioning and anti-rotation connection between the fastening sleeve 16 and the fixed copper busbar 15.

[0018] During operation, the connecting copper busbar 13 passes through the center of the current transformer 12 to conduct current. The current transformer 12 monitors current changes in real time to detect leakage. The connecting copper busbar 13, the fixing copper busbar 15, and the fastening sleeve 16 are fastened together by fasteners 19, ensuring the reliability of the electrical connection and low impedance characteristics. The opposing arrangement of the fixing copper busbar 15 and the fastening sleeve 16 via limiting posts 110 and limiting holes 111 effectively prevents relative displacement or rotation between components, enhancing the stability of the overall structure. Only the fastening holes 17 on the iron fastening sleeve 16 are tapped, avoiding common defects when tapping copper materials. Simultaneously, the overlapping copper busbar structure further improves mechanical strength and conductivity, enabling this connection structure to operate efficiently and safely in the leakage protection module.

[0019] The above embodiments are merely one preferred embodiment of the present utility model. Ordinary changes and substitutions made by those skilled in the art within the scope of the present utility model's technical solution are all included within the protection scope of the present utility model.

Claims

1. A connection structure for a leakage current protection module, comprising a contact mechanism and a current transformer, wherein a connecting copper busbar is disposed at the center of the current transformer and extends into the interior of the contact mechanism, characterized in that: The contact mechanism is provided with a fixing hole facing the connecting copper busbar, and a fixing copper busbar is fixed in the fixing hole. The upper end face of the fixing copper busbar is in contact with the connecting copper busbar, and a fastening sleeve is fixed on the lower end face of the fixing copper busbar. Fastening holes are provided at corresponding positions of the fastening sleeve, the fixing copper busbar and the connecting copper busbar, and only the fastening holes located on the fastening sleeve are tapped.

2. The connection structure of the leakage current protection module according to claim 1, characterized in that: The fastening sleeve is made of iron.

3. The connection structure of the leakage current protection module according to claim 1, characterized in that: The fastening sleeve has a protruding part on the end face that abuts against the fixed copper busbar. The protruding part is spliced ​​with the fastening hole and the protruding part is tapped.

4. The connection structure of the leakage current protection module according to claim 3, characterized in that: It also includes a fastener that mates with a fastening hole. The fastener includes a head and a bolt. The outer surface of the bolt is provided with threads. The head abuts against the end face of the connecting copper busbar that is opposite to the fixed copper busbar.

5. The connection structure of the leakage current protection module according to claim 3, characterized in that: The number of fastening holes is two, and they are respectively located at the center of the connecting copper busbar, the fixed copper busbar and the fastening sleeve. The corresponding end faces of the fixed copper busbar and the fastening sleeve are respectively provided with matching limiting posts and limiting holes. The limiting posts and limiting holes are respectively arranged opposite to each other on both sides of the fixed copper busbar and the fastening sleeve.

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