Double-shielding cable joint suitable for transformer end screen measurement

Abstract

The utility model provides a double-shielding cable joint suitable for transformer end screen measurement, comprising a grounding outer cylinder, the inner side of the first end of the grounding outer cylinder is provided with a grounding inner cylinder communicated with the grounding outer cylinder, the second end of the grounding outer cylinder is connected with the first end of an insulating cylinder, the second end of the insulating cylinder is connected with a first inner shielding cylinder, and the second end of the insulating cylinder is connected with a second inner shielding cylinder. A second inner shielding cylinder is installed in an inner cavity, close to the insulating cylinder side, of the first inner shielding cylinder, the second inner shielding cylinder is communicated with the first inner shielding cylinder, and a core wire cylinder which is not communicated with the first inner shielding cylinder and the second inner shielding cylinder is installed in an inner cavity, away from the insulating cylinder side, of the first inner shielding cylinder. The center of the core wire cylinder is provided with an installation hole which is used for installing a high-voltage test cable core wire and is of a blind hole structure. The center hole of the second inner shielding cylinder is communicated with the installation hole. The cable is fixed through the locking joint, and meanwhile, the core wire, the inner shielding layer and the outer shielding layer of the high-voltage test wire can be arranged on the same cable joint, so that the danger degree of connecting the cable joint to high-voltage equipment is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of power measurement equipment, in particular to a double-shielded cable connector suitable for transformer end screen measurement. Background Art

[0002] According to the international standard IEC 76-3 (1980), "Power Transformers Part 3: Insulation Levels and Dielectric Tests," a transformer is a stationary electrical device that uses electromagnetic induction to convert AC voltage and current between two or more windings at the same frequency. Typically, the voltage and current values of each winding vary. High-voltage tests such as dielectric loss and insulation resistance are important for determining the insulation level of power transformers. These tests require good shielding of the test circuit and a high degree of assembly precision to ensure accurate and reliable testing.

[0003] At present, during the use of high-voltage test lines, there is a pressure difference between the core wire, inner shielding layer, and outer shielding layer. When using cable connectors without double shielding function, since the outer shielding wire is separated and grounded separately, there is high voltage between the outer shielding layer and the inner shielding layer, which makes it extremely dangerous for people to manually handle the cable connectors without double shielding function to plug and unplug the high-voltage equipment to be connected. Secondly, the double-shielded cable connectors in the existing technology use riveting and glue filling to connect the components. The assembly accuracy is not enough. When the voltage increases, the glue is easy to melt and the riveting is easy to break, which can easily cause the double-shielded cable connector to fall off. In addition, the surface of the connector is smooth, and the connector cannot be tightly fixed to the docking interface. This phenomenon increases the risk factor of the test, reduces the work efficiency of the test personnel, and affects the accuracy of the test results. Utility Model Content

[0004] The purpose of this utility model is to provide a double-shielded cable connector suitable for transformer end screen measurement. The cable is fixed by a locking connector. At the same time, the core wire, inner shield layer and outer shield layer of the high-voltage test line can be arranged on the same cable connector, reducing the risk of connecting the cable connector to high-voltage equipment. In order to achieve the above technical features, the purpose of this utility model is achieved as follows:

[0005] A double-shielded cable joint suitable for transformer end screen measurement, comprising a grounding outer cylinder, a grounding inner cylinder electrically connected to the grounding outer cylinder installed on the inner side of the first end of the grounding outer cylinder, the second end of the grounding outer cylinder is connected to the first end of the insulating cylinder, the second end of the insulating cylinder is connected to the first inner shielding cylinder, the first inner shielding cylinder is provided with a second inner shielding cylinder installed near the inner cavity of the insulating cylinder side, the second inner shielding cylinder is electrically connected to the first inner shielding cylinder, the first inner shielding cylinder is provided with a core wire cylinder which is not electrically connected to the first inner shielding cylinder and the second inner shielding cylinder away from the inner cavity of the insulating cylinder side, the core wire cylinder is provided with a mounting hole for mounting the core wire of a high-voltage test cable and is a blind hole structure, the center hole of the second inner shielding cylinder is connected to the mounting hole, the center hole of the insulating cylinder is respectively connected to the center hole of the second inner shielding cylinder and the center hole of the grounding inner cylinder, the first end of the grounding outer cylinder is connected to a locking joint, the locking joint is used to clamp on the outside of the outer insulation layer of the high-voltage test cable, and is used to clamp and lock the high-voltage test cable.

[0006] A through hole communicating with the mounting hole is provided on the side wall of the core wire barrel.

[0007] A first insulating sleeve is installed on the inner cavity of the first inner shielding tube away from the second inner shielding tube, a second insulating sleeve is provided between the second inner shielding tube and the first insulating sleeve, the core wire barrel is sleeved on the inner side of the first insulating sleeve, and the flange on the end portion of the core wire barrel close to the mounting hole is installed between the first insulating sleeve and the second insulating sleeve.

[0008] The locking joint includes a main body with one end threadedly connected to the grounding outer cylinder, and the other end of the main body is provided with a threaded section connected to the locking end cover, the end of the threaded section is provided with a plurality of tooth-shaped portions distributed in a circular array, the inner end of the locking end cover is a concave spherical structure, and the end of the tooth-shaped portion abuts against the spherical structure.

[0009] The end of the toothed portion is a convex spherical structure that matches the inner end of the locking end cover.

[0010] A rubber sleeve is installed on the inner side of the toothed portion.

[0011] The utility model has the following beneficial effects:

[0012] 1. The ground outer cylinder and the first inner shielding cylinder are insulated and connected through the insulating cylinder, and the first inner shielding cylinder and the core wire cylinder are insulated and connected through the first insulating sleeve and the second insulating sleeve, forming a stable step-like connection relationship and a reliable connection;

[0013] 2. During wiring, the outer shielding layer of the high-voltage test cable is conductively connected to the grounded inner barrel, the inner shielding layer is conductively connected to the second inner shielding barrel, and the core wire is conductively connected to the core wire barrel. This allows the core wire, inner shielding layer, and outer shielding layer of the high-voltage test cable to be arranged on the same cable connector, achieving a double-shielding effect for the cable connector and increasing the safety and accuracy of the test.

[0014] 3. Through the setting of the locking connector, tighten the locking end cover so that the concave spherical surface inside the locking end cover pushes the toothed part inward, thereby locking the high-voltage test cable and further stabilizing the cable connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] Figure 1 A cross-sectional view of a double-shielded cable connector suitable for transformer end screen measurement provided by an embodiment of the present utility model;

[0017] Figure 2 A schematic structural diagram of a core wire barrel provided in an embodiment of the present utility model;

[0018] Figure 3 An exploded view of a locking connector provided by an embodiment of the present invention;

[0019] In the figure: grounding outer tube 1, grounding inner tube 2, insulating tube 3, first inner shielding tube 4, second inner shielding tube 5, core wire tube 6, mounting hole 6a, through hole 6b, flange 6c, locking joint 7, main body 7a, threaded section 7a1, toothed portion 7a2, locking end cover 7b, rubber sleeve 7c, locking nut 7d, first insulating sleeve 8, second insulating sleeve 9. DETAILED DESCRIPTION

[0020] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0021] See attached Figure 1-3 In order to achieve the above technical features, the purpose of this utility model is achieved as follows:

[0022] A double-shielded cable connector suitable for transformer end screen measurement, comprising a grounding outer cylinder 1, a grounding inner cylinder 2 which is conductive with the grounding outer cylinder 1 is installed on the inner side of the first end of the grounding outer cylinder 1, a second end of the grounding outer cylinder 1 is connected to the first end of the insulating cylinder 3, the second end of the insulating cylinder 3 is connected to the first inner shielding cylinder 4, the first inner shielding cylinder 4 is close to the inner cavity of the insulating cylinder 3 and is provided with a second inner shielding cylinder 5, the second inner shielding cylinder 5 is conductive with the first inner shielding cylinder 4, and the first inner shielding cylinder 4 is away from the inner cavity of the insulating cylinder 3 and is provided with a second inner shielding cylinder 5 which is conductive with the first inner shielding cylinder 4. The first inner shielding tube 4 and the second inner shielding tube 5 are both non-conductive core wire tubes 6. The center of the core wire tube 6 is provided with a blind hole mounting hole 6a for mounting the core wire of the high-voltage test cable. The center hole of the second inner shielding tube 5 is connected to the mounting hole 6a. The center hole of the insulating tube 3 is respectively connected to the center hole of the second inner shielding tube 5 and the center hole of the grounding inner tube 2. The first end of the grounding outer tube 1 is connected to the locking connector 7. The locking connector 7 is used to clamp on the outside of the outer insulation layer of the high-voltage test cable and is used to clamp and lock the high-voltage test cable. The high-voltage test line includes an outer insulation layer, a metal mesh outer shielding layer, a high-temperature resistant insulation layer, a metal mesh inner shielding layer, a core wire insulation layer, and a core wire from the outside to the inside. The wiring process of the connector of the present application is: the high-voltage test cable passes through the locking connector 7 and enters the grounding inner tube 2, the outer insulation layer is stripped off, the metal mesh outer shielding layer is welded to the grounding inner tube 2, and then passes through the insulation tube 3 to enter the second inner shielding tube 5, the high-temperature resistant insulation layer is stripped off, and the metal mesh inner shielding layer is conductively connected to the second inner shielding tube 5; the core wire after stripping the core wire insulation layer is inserted into the mounting hole 6a of the core wire barrel 6 and is conductively connected to the core wire barrel 6, and finally the high-voltage test cable is clamped by the locking connector 1 to avoid derailment.

[0023] Furthermore, a through hole 6b is provided on the side wall of the core wire barrel 6 and is communicated with the mounting hole 6a. The through hole 6b is used as a welding hole to fix the core wire in the mounting hole 6a by welding.

[0024] Furthermore, a first insulating sleeve 8 is installed in the inner cavity of the first inner shielding tube 4 away from the second inner shielding tube 5, and a second insulating sleeve 9 is provided between the second inner shielding tube 5 and the first insulating sleeve 8. The core wire barrel 6 is sleeved on the inner side of the first insulating sleeve 8, and the flange 6c on the end portion of the core wire barrel 6 close to the mounting hole 6a is installed between the first insulating sleeve 8 and the second insulating sleeve 9, thereby forming a structure in which the core wire barrel 6 is not conductive with the first inner shielding tube 4 and the second inner shielding tube 5.

[0025] Furthermore, the locking connector 7 includes a main body 7a, one end of which is threadedly connected to the grounding outer cylinder 1, and the other end of the main body 7a is provided with a threaded section 7a1 connected to the locking end cover 7b. The end of the threaded section 7a1 is provided with a plurality of tooth-shaped portions 7a2 distributed in a circular array. The inner end of the locking end cover 7b is a concave spherical structure, and the end of the tooth-shaped portion 7a2 abuts against the spherical structure. By tightening the locking end cover 7b, the concave spherical surface inside the locking end cover 7b pushes the tooth-shaped portion 7d inward, thereby locking the high-voltage test cable.

[0026] Furthermore, the end of the tooth-shaped portion 7a2 is a convex spherical structure that matches the inner end of the locking end cover 7b, so as to facilitate the inward deformation of the tooth-shaped portion 7d and achieve the purpose of rapid tightening.

[0027] Furthermore, a rubber sleeve 7c is installed on the inner side of the tooth-shaped portion 7a2 to increase the supporting surface of the tooth-shaped portion 7a2 after shrinkage and deformation, thereby playing an anti-slip and anti-slip role.

Claims

1. A double-shielded cable connector suitable for transformer end screen measurement, characterized by: The invention comprises a grounding outer tube (1), a grounding inner tube (2) which is in electrical communication with the grounding outer tube (1) is installed on the inner side of the first end of the grounding outer tube (1), the second end of the grounding outer tube (1) is connected to the first end of the insulating tube (3), the second end of the insulating tube (3) is connected to the first inner shielding tube (4), the first inner shielding tube (4) is provided with a second inner shielding tube (5) which is close to the inner cavity of the insulating tube (3), the second inner shielding tube (5) is in electrical communication with the first inner shielding tube (4), the first inner shielding tube (4) is provided with a second inner shielding tube (4) which is away from the inner cavity of the insulating tube (3), The second inner shielding tube (5) is a non-conductive core wire tube (6), and a mounting hole (6a) of a blind hole structure for mounting the core wire of the high-voltage test cable is provided at the center of the core wire tube (6). The center hole of the second inner shielding tube (5) is connected to the mounting hole (6a), and the center hole of the insulating tube (3) is respectively connected to the center hole of the second inner shielding tube (5) and the center hole of the grounding inner tube (2). The first end of the grounding outer tube (1) is connected to a locking joint (7), and the locking joint (7) is used to clamp on the outside of the outer insulation layer of the high-voltage test cable, and is used to clamp and lock the high-voltage test cable.

2. A double-shielded cable connector suitable for transformer end screen measurement according to claim 1, characterized in that: A through hole (6b) that penetrates the mounting hole (6a) is provided on the side wall of the core wire barrel (6).

3. The double-shielded cable connector suitable for transformer end screen measurement according to claim 2, characterized in that: A first insulating sleeve (8) is installed in the inner cavity of the first inner shielding tube (4) away from the second inner shielding tube (5), a second insulating sleeve (9) is provided between the second inner shielding tube (5) and the first insulating sleeve (8), the core wire barrel (6) is sleeved on the inner side of the first insulating sleeve (8), and the end flange (6c) of the core wire barrel (6) close to the mounting hole (6a) is installed between the first insulating sleeve (8) and the second insulating sleeve (9).

4. The double-shielded cable connector suitable for transformer end screen measurement according to claim 3, characterized in that: The locking joint (7) comprises a main body (7a) having one end threadedly connected to the grounding outer cylinder (1); the other end of the main body (7a) is provided with a threaded section (7a1) connected to the locking end cover (7b); the end of the threaded section (7a1) is provided with a plurality of tooth-shaped portions (7a2) distributed in a circular array; the inner end of the locking end cover (7b) is a concave spherical structure, and the end of the tooth-shaped portion (7a2) abuts against the spherical structure.

5. The double-shielded cable connector suitable for transformer end screen measurement according to claim 4, characterized in that: The end of the tooth-shaped portion (7a2) is a convex spherical structure that matches the inner end of the locking end cover (7b).

6. The double-shielded cable connector suitable for transformer end screen measurement according to claim 5, characterized in that: A rubber sleeve (7c) is installed on the inner side of the toothed portion (7a2).

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