Voltage transformer

Abstract

The utility model relates to the technical field of transformers, in particular to a voltage transformer. Comprising a main body, two terminals are arranged on the main body, each terminal comprises a connecting pipe, a connecting cavity is formed in each connecting pipe, and an L-shaped groove is formed in the inner wall of each connecting pipe; the connecting sliding ring is arranged in the connecting cavity in a sliding manner, and a convex part matched with the L-shaped groove is arranged on the connecting sliding ring; the clamping rod is hinged to the inner side of the connecting sliding ring, an abutting rod is arranged on the side face of the clamping rod, and a pricking needle is arranged at the end of the clamping rod; according to the utility model, the voltage transformer terminal structure which has a quick connection / disassembly function and is stable in clamping is realized.

Description

Technical Field

[0001] This utility model relates to the technical field of transformers, and more particularly to a voltage transformer. Background Technology

[0002] Voltage transformers, as core measuring devices in power systems and industrial automation, are primarily used to convert high voltage to low voltage (such as the standard 100V) at a fixed ratio, providing accurate voltage signals for metering instruments and relay protection devices. Their operational stability and wiring reliability directly affect the safe operation and maintenance of the power system and the accuracy of data. Among these components, the terminals, as the connection interface between the voltage transformer and external cables, are crucial for signal transmission; their structural design directly determines the efficiency, stability, and safety of the cable connection.

[0003] In existing technologies, the connection between the terminals of voltage transformers and cables mostly adopts traditional mechanical connection methods, such as bolt fastening, welding, and crimping. These methods have many problems that need to be solved in practical applications, as follows:

[0004] 1. The connection and disassembly operations are cumbersome and inefficient.

[0005] The mainstream connection method for existing terminals is bolt fastening: when wiring, the outer sheath of the cable end must be stripped first, the inner core is wrapped or laid flat on the terminal post, and then the fastening bolt is tightened with a wrench or other tools to ensure contact between the cable and the terminal; when disassembling, the bolt must be loosened in the opposite direction to remove the cable. The whole process relies on special tools and the operation steps are cumbersome. Especially in installation scenarios with limited space, such as power cabinets and distribution boxes, tool access is limited, and a single wiring or maintenance often takes 5-10 minutes, which seriously affects the work efficiency for batch equipment debugging or emergency fault repair. In addition, although welding connections can achieve stable conductivity, the welding process requires professional operation, and the high temperature required to melt the solder joint during disassembly can easily damage the terminal and cable, which cannot meet the needs of frequent disassembly or temporary wiring; crimping connections require special crimping pliers, and after crimping, the terminal and cable form a fixed connection. Subsequent maintenance requires cutting the cable and re-crimping, resulting in material waste and increased time costs.

[0006] 2. Poor clamping stability, easily loosened by external factors.

[0007] Traditional terminal clamping structures are mostly designed with "single bolt clamping" or "double clamping," resulting in few clamping points and uneven force distribution. During long-term operation, factors such as power system vibration (e.g., mechanical vibration generated by transformers and motors) and environmental temperature changes (e.g., thermal expansion and contraction of materials due to high summer temperatures and low winter temperatures) can cause bolts to loosen or clamping elasticity to decrease, leading to a decrease in contact pressure between the cable and the terminal, or even the appearance of gaps. This loosening increases contact resistance and generates localized heating during current transmission. This not only causes voltage signal attenuation or distortion, affecting the accuracy of metering and protection devices, but in severe cases, excessive heating can also lead to insulation aging, short circuits, and other safety hazards, threatening the stable operation of the power system.

[0008] In summary, existing voltage transformer terminals have significant shortcomings in terms of connection efficiency, clamping stability, conductivity reliability, operational safety, and cable compatibility, failing to meet the requirements of efficient operation and maintenance, safe operation, and multi-scenario adaptability in power systems. Therefore, developing a voltage transformer terminal structure with rapid connection / disconnection capabilities, stable clamping, and reliable conductivity has become an urgent technical problem to be solved in this field. Utility Model Content

[0009] The purpose of this invention is to address the aforementioned technical problems by providing a voltage transformer with quick connection / disconnection capabilities and stable clamping.

[0010] In view of this, the present invention provides a voltage transformer, including a main body, the main body having two terminals, the terminals including:

[0011] The connecting pipe has a connecting cavity inside and an L-shaped groove on its inner wall.

[0012] A connecting slip ring is slidably disposed within the connecting cavity, and the connecting slip ring has a protrusion that mates with the L-shaped groove;

[0013] The clamping rod is hinged to the inside of the connecting slip ring, and has an abutment rod on its side. The end of the clamping rod is equipped with a needle.

[0014] Furthermore, the abutment rod is circular in shape.

[0015] Furthermore, there are at least three clamping rods.

[0016] Furthermore, a wedge-shaped portion is provided on the side of the clamping rod near the side wall of the connecting cavity.

[0017] Furthermore, it also includes:

[0018] An insulating layer is provided on the outside of the connecting pipe.

[0019] Furthermore, the clamp includes an arc-shaped portion, which is elastic.

[0020] At least one air intake channel and one air outlet channel are provided. The beneficial effects of this invention are:

[0021] 1. This utility model realizes a voltage transformer terminal structure with quick connection / disassembly function, stable clamping, and reliable conductivity.

[0022] 2. This utility model uses the surface of the circular contact rod to make contact with the cable as a surface contact, which can significantly increase the contact area and reduce the contact resistance. At the same time, the circular structure can make the contact force on the cable more uniform, avoid local stress concentration that could lead to damage to the cable sheath, and enhance the stability and reliability of the contact process. Attached Figure Description

[0023] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0024] Figure 2 This is a three-dimensional structural diagram of the terminal of this utility model;

[0025] Figure 3 This is a schematic diagram of the wedge-shaped part of this utility model;

[0026] Figure 4 This is a schematic diagram of the arc-shaped part of this utility model.

[0027] The markings in the diagram are as follows:

[0028] 1. Main body; 2. Terminal; 3. Connecting tube; 4. L-shaped groove; 5. Connecting slip ring; 6. Clamping rod; 7. Abutting rod; 8. Needle; 9. Wedge-shaped part; 10. Insulating layer; 11. Arc-shaped part. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0030] This embodiment provides a voltage transformer with quick connection and disconnection functions. Its core structure revolves around "body 1 - terminal 2", aiming to solve the problems of cumbersome and inefficient cable connection operations in traditional voltage transformers. The transformer body 1 is integrally molded from high-strength insulating material, internally encapsulating core transformer components such as the iron core and windings. Two clearly defined terminals 2 are symmetrically arranged at the top of the body 1: an input terminal 2 for connecting the voltage to be tested and an output terminal 2 for outputting the converted standard voltage. The mechanical structure and conductivity of the two terminals 2 are completely identical; their functions are distinguished only by their installation location and wiring markings.

[0031] Terminal 2 is made entirely of a high-conductivity metal conductor (such as copper alloy) to ensure stable current transmission and low loss. Its structure consists of three key components: connecting tube 3, connecting slip ring 5, and clamping rod 6. These components work together to achieve rapid cable fixing and conductive connection.

[0032] Connecting tube 3: Serving as the outer support structure of terminal 2, it is a hollow cylinder with an internal cavity for accommodating the cable, connecting slip ring 5, and clamping rod 6. The inner diameter of the connecting cavity is designed according to the specifications of the compatible cable to ensure both sufficient operating clearance after cable insertion and stability of subsequent clamping. An L-shaped groove is carefully machined on the inner wall of the connecting tube 3. This groove consists of two vertically connected sections: one section is circumferentially arranged along the circumference of the connecting tube 3, with a length approximately 1 / 4 to 1 / 3 of the circumference of the inner wall of the connecting tube 3, used for circumferential positioning of the connecting slip ring 5; the other section is axially arranged along the length of the connecting tube 3, extending from the port of the connecting tube 3 to the beginning of the circumferential groove, serving as the axial sliding channel for the connecting slip ring 5. To ensure that the connecting slip ring 5 is subjected to balanced force and moves stably, at least two L-shaped grooves are provided and are evenly distributed along the circumference of the inner wall of the connecting pipe 3 (e.g., 3 or 4 grooves are provided at intervals of 120° or 90°). The depth and width of the grooves must match the protrusions on the connecting slip ring 5 to ensure that the protrusions can slide smoothly without significant shaking.

[0033] The connecting slip ring 5 has a ring-shaped structure and is coaxially arranged with the connecting pipe 3 within the connecting cavity. It is assembled using a clearance fit, allowing it to slide freely along the axial direction of the connecting pipe 3 (achieving a "push-pull" action) and rotate radially around its own axis (achieving a "rotational positioning" action). On the outer wall of the connecting slip ring 5, corresponding to the L-shaped groove on the inner wall of the connecting pipe 3, there is an integrally formed outwardly protruding part. The number and shape of the protrusions perfectly match the L-shaped groove. When the connecting slip ring 5 moves within the connecting cavity, the protrusions are always embedded in the groove, providing guidance and limiting for the movement of the connecting slip ring 5. The inner side of the connecting slip ring 5 (the side closest to the axis of the connecting cavity) is machined with evenly distributed hinge seats for mounting the clamping rods 6. The number of hinge seats is the same as the number of clamping rods 6, and a wear-resistant metal hinge structure is used to ensure that the clamping rods 6 can rotate flexibly without being easily damaged.

[0034] Clamping rod 6: As a component that directly clamps the cable and achieves conductive connection, it is made of elastic conductive metal and has at least three (preferably 3-4) evenly distributed along the inner circumference of the connecting slip ring 5, forming a clamping structure similar to a "three-jaw chuck" to ensure uniform force on the cable and avoid cable loosening or damage due to uneven force. One end of each clamping rod 6 is hinged to the inner hinge seat of the connecting slip ring 5, allowing the clamping rod 6 to rotate about the hinge point in a direction closer to or away from the axis of the connecting cavity (achieving "opening-closing" action); A contact rod 7 is vertically fixed on the middle side of the clamping rod 6 (the side away from the inner wall of the connecting tube 3). The contact rod 7 adopts a circular cylindrical structure with a diameter slightly larger than the thickness of the clamping rod 6. When the cable is inserted into the connecting cavity, the contact rod 7 will first contact the outer sheath of the cable (or the inner core after the outer sheath has been stripped). The other end of the clamping rod 6 (the end away from the hinge end) is machined with a barbed needle 8. The barbed needle 8 faces the axis of the connecting tube 3, with a sharp tip. Its length is designed according to the thickness of the cable sheath to ensure that it can easily penetrate the cable sheath and contact the internal metal core to achieve reliable conductivity.

[0035] Cable connection and disconnection working principle

[0036] Connection process

[0037] Cable insertion: First, depending on the cable specifications, if the cable sheath is thick, a small amount of sheath can be stripped from the end beforehand (exposing the inner core). Then, insert the cable end into the connecting cavity from the port of the connecting tube 3 until the cable end abuts the bottom of the connecting cavity (or reaches the preset insertion depth). During this process, the cable will contact the circular abutment rod 7 on the clamp 6. As the cable continues to be inserted, the abutment rod 7 is subjected to the squeezing force of the cable.

[0038] Clamping rod 6 retracts and needle 8 pierces: After the contact rod 7 is pressed against by the cable, it will drive the clamping rod 6 to rotate inward (close to the axis) around the hinge point, causing multiple clamping rods 6 to retract synchronously and gradually fit against the cable surface. At the same time, the needle 8 on the end of the clamping rod 6 will penetrate the outer sheath of the cable during the retraction process (or make direct contact if the outer sheath has been stripped), and finally pierce into the metal core of the cable, achieving the initial positioning of mechanical fixation and conductive connection.

[0039] Slip ring advance and rotation positioning: Hold the cable steady with one hand, and push the connecting slip ring 5 inward along the axis of the connecting tube 3 (towards the current transformer body 1). The connecting slip ring 5 drives the clamping rod 6, which is hinged to it, and the clamped cable to move inward synchronously until the protrusion on the connecting slip ring 5 slides from the axial section of the L-shaped groove into the starting position of the circumferential section. Then, rotate the cable (because the clamping rod 6 is in close contact with the cable, rotating the cable will drive the connecting slip ring 5 to rotate synchronously), so that the protrusion slides to the end in the circumferential section. At this time, the connecting slip ring 5 is limited by the structure of the L-shaped groove and can no longer slide outward along the axis, thus firmly fixing the cable in the terminal 2, completing the entire connection process.

[0040] Disassembly process

[0041] Quick disassembly can be achieved by reversing the operation: rotate the cable so that the protrusion on the connecting slip ring 5 slides from the circumferential section of the L-shaped groove 4 back to the starting position of the axial section. Then pull the connecting slip ring 5 outward, causing the clamping rod 6 to move outward synchronously with the cable. The clamping rod 6 is no longer constrained by the connecting cavity and opens outward under its own elasticity (or with slight external force assistance). The needle 8 disengages from the inner core of the cable, the contact rod 7 separates from the cable, and finally the cable is pulled out of the connecting cavity.

[0042] Conductivity optimization design

[0043] To further improve the conductivity between terminal 2 and the cable and avoid problems such as increased resistance and overheating caused by poor contact, both the clamp 6 and the connecting slip ring 5 are made of high-purity conductive metal. Conductive liquid material, preferably conductive silver paste, can be added to the contact points between the clamp 6 and the cable, and to the gaps between the connecting slip ring 5 and the connecting tube 3. Conductive silver paste uses silver powder as a conductive filler and has excellent conductivity and adhesion. Its adhesive medium is a self-adhesive liquid, which ensures long-term stable conductivity and avoids component adhesion due to curing, facilitating subsequent disassembly and maintenance. The self-adhesive conductive silver paste can also fill the tiny gaps between the clamp 6 and the cable, increasing the actual conductive contact area, while also providing some anti-oxidation and anti-corrosion effects, extending the service life of terminal 2.

[0044] Key component functional advantages

[0045] Circular contact rod 7: Compared with the traditional square or flat contact structure, the surface of the circular contact rod 7 makes surface contact with the cable (circular cross-section), which can significantly increase the contact area and reduce the contact resistance. At the same time, the circular structure can make the contact force on the cable more uniform, avoid local stress concentration that could lead to cable sheath damage, and enhance the stability and reliability of the contact process.

[0046] Multi-clamp rod design: Three or more clamp rods 6 are set to form a multi-point uniform clamping structure, which can apply a stable clamping force to the cable from different directions. Even if the cable is subjected to slight external pulling or vibration, it is not easy to shift or loosen, which greatly improves the anti-interference ability and stability of the cable connection.

[0047] Example 2:

[0048] The voltage transformer provided in this embodiment, while fully inheriting all the technical solutions of Embodiment 1 (including the structure of the main body 1, the connecting tube 3 of the terminal 2, the connecting slip ring 5, the clamping rod 6, the contact rod 7, the needle 8 and other structures and quick connection / disassembly functions), has been further optimized in terms of clamping stability, operational safety and conductivity. Three key enhancement structures have been added to make the overall performance of the transformer more adaptable to the needs of complex working conditions.

[0049] New technical features refined

[0050] Wedge-shaped part 9 design of clamping rod 6: A wedge-shaped part 9 is machined on the side of each clamping rod 6 near the side wall of the connecting cavity (i.e., near the inner wall of the connecting tube 3). The wedge-shaped part 9 is "sloping" in shape, gradually tilting towards the side wall of the connecting cavity from the middle of the clamping rod 6 towards the end (in the direction of the needle 8), forming a wedge-shaped structure with the tip facing the port of the connecting tube 3. When the clamping rod 6 is driven inward by the connecting slip ring 5 and pushed into the connecting cavity with the slip ring, the wedge-shaped part 9 will form a squeezing fit with the inner wall of the connecting tube 3—the inner wall of the connecting tube 3 generates a reaction force in the axial direction on the wedge-shaped part 9. This force will further enhance the clamping force of the clamping rod 6 on the cable, making the clamping rod 6 fit the cable more tightly. This design can effectively avoid the loosening of the cable due to vibration, thermal expansion and contraction and other factors during long-term use, greatly improving the stability and reliability of cable fixing, and is especially suitable for industrial environments with high vibration and high stability requirements. Insulation layer 10 covering the connecting tube 3: To improve operational safety and prevent electric shock accidents caused by accidental contact with the metal connecting tube 3 during wiring and maintenance, an insulation layer 10 is completely covered on the outer surface of the connecting tube 3. The insulation layer 10 is made of high-temperature resistant, aging-resistant, and excellent insulating materials (such as silicone rubber, epoxy resin, etc.), with a thickness designed according to the voltage level (usually 1-3mm) to ensure effective current conduction blocking. The surface of the insulation layer 10 can also be processed with anti-slip texture to increase the friction between the hand and the connecting tube 3, making it easier for the operator to grip the terminal 2 when pushing and rotating the connecting slip ring 5, thus improving operational convenience. At the same time, the insulation layer 10 also provides a certain degree of protection for the connecting tube 3, preventing it from oxidizing and corroding due to external environmental factors (such as moisture and dust), and extending the service life of the terminal 2. The curved portion 11 of the clamping rod 6 and its elastic design: The structure of the clamping rod 6 is optimized by designing the inner side (closer to the cable) of the clamping rod 6 as a curved portion 11. The radius of curvature of the curved portion 11 matches the outer diameter of the compatible cable, upgrading the contact between the clamping rod 6 and the cable surface from "line contact" to "surface contact," significantly increasing the conductive contact area, effectively reducing contact resistance, and minimizing energy loss and heat generation during current transmission. Simultaneously, the clamping rod 6 is made entirely of a conductive metal material with good elasticity (such as beryllium bronze alloy), giving it a certain degree of elastic deformation capability: when clamping the cable, the curved portion 11 can better conform to the cable surface through elastic deformation, compensating for even slight deviations in the cable's outer diameter and ensuring stable contact; when disassembling the cable, the clamping rod 6 can automatically open under the action of elastic restoring force, without requiring additional external force, further improving the ease of disassembly. Furthermore, the elastic design can buffer the instantaneous impact force on the cable, preventing damage to the clamping rod 6 or the spike 8 due to sudden pulling, enhancing the structural durability of the terminal 2.

[0051] The voltage transformer in this embodiment retains the core advantages of quick connection and quick disassembly of Embodiment 1. It enhances clamping stability through the wedge-shaped part 9, improves operational safety through the insulation layer 10, and optimizes conductivity and adaptability through the arc-shaped part 11 and elastic design. This results in a voltage transformer with more comprehensive functions and more reliable performance, which can be widely used in various scenarios such as power systems, industrial automation, and electrical equipment testing. It is especially suitable for occasions with high requirements for operational efficiency, connection stability, and safety.

[0052] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms fall within the scope of protection of this application.

Claims

1. A voltage transformer, comprising a main body (1) having two terminals (2) on the main body (1), characterized in that, Terminal (2) includes: Connecting pipe (3), the connecting pipe (3) is provided with a connecting cavity, and the inner wall of the connecting pipe (3) is provided with an L-shaped groove (4); A connecting slip ring (5) is slidably disposed in the connecting cavity, and the connecting slip ring (5) is provided with a protrusion that mates with the L-shaped groove (4); The clamping rod (6) is hinged to the inner side of the connecting slip ring (5), and an abutting rod (7) is provided on the side of the clamping rod (6). The end of the clamping rod (6) is provided with a needle (8).

2. A voltage transformer according to claim 1, characterized in that, The abutment rod (7) is circular in shape.

3. A voltage transformer according to claim 1, characterized in that, There are at least three clamps (6).

4. A voltage transformer according to claim 1, characterized in that, The clamping rod (6) has a wedge-shaped part (9) on the side near the side wall of the connecting cavity.

5. A voltage transformer according to claim 1, characterized in that, Also includes: An insulating layer (10) is provided outside the connecting pipe (3).

6. A voltage transformer according to claim 1, characterized in that, The clamp (6) includes an arc-shaped portion (11) which is elastic.

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