A test fixture for shielding effectiveness wire injection method

Abstract

This utility model relates to a shielding effectiveness wire injection method testing fixture, including a base plate, on the top of which are two sets of transmitting devices. Each transmitting device consists of a fixed plate, a first N-head wall panel connector, a coaxial cable bracket, and a transmitter. The fixed plate is fixedly mounted on the base plate. The first N-head wall panel connector is located near the rear end of the fixed plate, and the coaxial cable bracket is located near the front end of the fixed plate. The transmitter is fixedly mounted on the fixed plate on one side in front of the coaxial cable bracket. A cable connection box and a resistor shielding box are located on the front side of the base plate near both sides. This shielding effectiveness wire injection method testing fixture allows for flexible replacement of the clamping replacement block in the transmitter, making it flexible in use. The spacing between the two sets of transmitting devices can be flexibly adjusted, and the connecting blocks on the cable connection box and resistor shielding box can be replaced according to the type of test piece to adapt to the connection of cables or connectors, demonstrating strong versatility.

Description

Technical Field

[0001] This utility model relates to the wire injection method for testing the shielding effectiveness of high-voltage cables in electric vehicles, and more particularly to a testing fixture for the wire injection method for shielding effectiveness. Background Technology

[0002] With the development of electric vehicles, the electromagnetic environment inside automobiles is becoming increasingly complex. Using shielded cables can reduce radio frequency electromagnetic emissions from devices and improve their electromagnetic interference immunity. For high-voltage devices, such as power batteries, shielded wire harnesses are also used in the transmission lines of high-speed digital systems as electric vehicles become more intelligent and connected. The main testing method for the shielding effectiveness of automotive shielded wire harnesses is the wire injection method.

[0003] The line injection method involves applying a known current and voltage to the shield of the cable under test, while simultaneously testing the induced voltage between the cable core and the shield. By combining this with the equivalent circuit diagram of the line injection method, the transfer impedance and shielding performance of the cable under test can also be calculated.

[0004] Shielding effectiveness is typically defined based on the electrical length of the cable. Surface transfer impedance reflects the shielding effectiveness during short electrical periods, while shielding attenuation indicates the shielding effectiveness over long electrical periods. When using the wire injection method, the injection wire can be attached to different locations on the surface of the cable under test. If the cable's shielding layer is uniform, the test results at different locations should be consistent. The wire injection method can be used for testing at both the far and near ends, and matching circuits can also be employed.

[0005] The advantages of wire injection testing include its ability to provide accurate test results and its lower cost compared to other methods. Furthermore, wire injection testing is also suitable for testing high-voltage shielded cables, high-voltage shielded harnesses, and high-voltage shielded connectors.

[0006] However, existing wire injection testing fixtures have fixed transmitter structures and positions, and can only be used for a single type of cable or wire harness. When testing cables or wire harnesses of different diameters, corresponding transmitters need to be matched, and the positions of the transmitters are fixed and cannot be adjusted according to the length of the cable or wire harness being tested. In addition, the shielding box has a single function. Testing the shielding effectiveness of cables and connectors requires shielding boxes with corresponding structures that facilitate connection, which increases design and usage costs and makes the use inflexible. Summary of the Invention

[0007] The technical problem to be solved by this utility model is to provide a flexible and versatile testing fixture for the shielding effectiveness line injection method.

[0008] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0009] A shielding effectiveness wire injection method testing fixture includes a base plate, which is a rectangular strip structure. Two sets of transmitting devices are symmetrically arranged on the top of the base plate along its left-right length. Each transmitting device consists of a fixed plate, a first N-head wall panel connector, a coaxial cable bracket, and a transmitter. The fixed plate is fixedly mounted on the base plate. The first N-head wall panel connector is mounted on the fixed plate near its rear end via an N-head bracket. A coaxial cable bracket corresponding to the first N-head wall panel connector is located near the front end of the fixed plate. The transmitter is fixedly mounted on the fixed plate. Located on one side directly in front of the coaxial cable bracket, the two sets of transmitters on the two sets of transmitter devices are symmetrical from left to right; the front of the base plate is provided with cable connection boxes and resistor shielding boxes near both sides, the cable connection boxes and resistor shielding boxes are corresponding to each other, and the two sets of transmitters are located between the corresponding cable connection boxes and resistor shielding boxes; each end of the cable connection box and resistor shielding box is provided with a flange, and the two flanges are respectively installed on the cable connection box and resistor shielding box through two connecting blocks; the other end of the cable connection box corresponding to its end flange is provided with a second N-head wall panel connector.

[0010] Furthermore, the top of the base plate is provided with multiple vertical studs along its length, and the fixing plate is provided with connecting holes that fit with the studs. After the fixing plate is fitted onto the studs, it is fixed to the base plate by nuts that fit with the studs.

[0011] Furthermore, the top center of the coaxial cable bracket is provided with a coaxial clamping hole that is connected front and back, and the coaxial clamping hole corresponds to the front and back of the first N-head wall panel connector; the top of the coaxial cable bracket is provided with a cable cover that is fixedly connected thereto.

[0012] Furthermore, the transmitter includes an external mounting frame. The center of the end of the external mounting frame is provided with a top-opening and front-to-back communicating assembly groove. A clamping replacement block is embedded in the assembly groove. The top of the clamping replacement block is provided with a partition plate fixedly connected to the top of the external mounting frame. The center of the end of the partition plate is provided with a coaxial cable outlet hole that is front-to-back communicating. A groove is provided at the top of the partition plate near the front end. A silicone pressure block that mates with the groove is provided in the groove. The bottom of the silicone pressure block is provided with a downward-opening and front-to-back communicating wire pressing groove. The end of the wire pressing groove has a semi-circular structure, which corresponds vertically to the coaxial cable outlet hole.

[0013] Furthermore, the top center of the clamping replacement block is provided with a clamping hole that is connected from front to back. The clamping hole has a "U" shaped structure and a semi-circular structure at the bottom. The diameter of the semi-circle is 4-20mm.

[0014] Furthermore, the top of the partition is provided with a threaded hole that communicates vertically with the coaxial cable outlet hole, and a grounding screw that engages with the threaded hole is provided in the threaded hole, with the lower end of the grounding screw located inside the coaxial cable outlet hole.

[0015] Furthermore, the cable connection box includes a connection box body with a three-dimensional rectangular structure, a connection cavity with a top opening inside the connection box body, and a detachable connection box cover on the top; the front end of the connection box body is provided with a first guide hole that communicates internally and externally, and a connecting block for connecting a connector is fixed outside the first guide hole; the rear end of the cable connection box is provided with an assembly hole that communicates internally and externally, and the second N-head wall panel connector is fixedly installed inside the second N-head wall panel connector.

[0016] Furthermore, the resistor shielding box includes a shielding box body with a three-dimensional rectangular structure, a shielding cavity with a top opening inside the shielding box body, and a detachable shielding box cover on the top; the front end of the shielding box body is provided with a second guide hole that communicates internally and externally, and a connecting block for connecting a granite head is fixed outside the second guide hole.

[0017] Furthermore, the end center of the connecting block is provided with a threaded connection hole that connects the front and rear, and the granite head is screwed into the threaded connection hole.

[0018] Compared with the prior art, the advantages of this utility model are: this shielding effectiveness line injection method test fixture is flexible and adjustable, and the clamping replacement block in the transmitter can be flexibly replaced according to the diameter of the cable. It is flexible in use, and the spacing between the two sets of symmetrical transmitters can be flexibly adjusted. It can perform coupling length tests on 0.5m and 0.3m cables. Moreover, the connecting blocks on the cable connection box and the resistor shielding box can be replaced according to the type of test piece to adapt to the connection of cables or connectors, and it has strong versatility. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a test fixture for the shielding effectiveness line injection method according to this utility model;

[0021] Figure 2 This is a schematic diagram of the cable assembly for a shielding effectiveness wire injection method test fixture according to this utility model;

[0022] Figure 3This is a schematic diagram of the transmitting device structure in a shielding effectiveness line injection method testing fixture of this utility model;

[0023] Figure 4 This is a schematic diagram of the transmitter axial structure in a shielding effectiveness line injection method testing fixture of this utility model;

[0024] Figure 5 This is a sectional view of the transmitter side structure in a shielding effectiveness line injection method testing fixture of this utility model;

[0025] Figure 6 This is a schematic diagram of the clamping replacement block structure in a shielding effectiveness line injection method testing fixture of this utility model;

[0026] Figure 7 This is a schematic diagram of the external structure of the cable connection box in a test fixture for the shielding effectiveness line injection method of this utility model;

[0027] Figure 8 This is a sectional view of the side structure of the cable connection box in the shielding effectiveness wire injection method testing fixture of this utility model;

[0028] Figure 9 This is a schematic diagram of the internal structure of the cable connection box in a test fixture for the shielding effectiveness line injection method of this utility model;

[0029] Figure 10 This is a schematic diagram of the external structure of the resistor shielding box in a test fixture for the shielding effectiveness line injection method according to this utility model;

[0030] Figure 11 This is a sectional view of the side structure of the resistor shielding box in the shielding effectiveness line injection method testing fixture of this utility model;

[0031] Figure 12 This is a schematic diagram of the connecting block structure in a shielding effectiveness line injection method testing fixture of this utility model.

[0032] In the diagram: 1. Base plate; 11. Stud; 2. Transmitter; 21. Fixing plate; 22. N-head bracket; 221. First N-head wall panel connector; 23. Coaxial cable bracket; 231. Coaxial clamping hole; 232. Cable cover; 24. Transmitter; 241. External fixing bracket; 2411. Assembly slot; 242. Clamping replacement block; 2421. Clamping hole; 243. Upper pressure plate; 2431. Partition plate; 2432. Grounding top screw; 244. Silicone clamping block; 2 441. Coaxial cable outlet hole; 3. Cable connector box; 30. Connector box cover; 31. Connector box body; 311. Connecting cavity; 312. First guide hole; 313. Assembly hole; 32. Second N-head wall panel connector; 4. Resistor shielding box; 40. Shielding box cover; 41. Shielding box body; 411. Shielding cavity; 412. Second guide hole; 5. Test cable; 6. Coaxial cable; 7. Injection wire; 8. Gravel connector; 9. Connecting block; 91. Threaded connection hole. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the embodiments of the present invention, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate orientation or positional relationships based on the orientation or positional relationships shown in the drawings, or the orientation or positional relationships commonly used when the product of the present invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0035] Furthermore, the use of terms such as "horizontal" or "vertical" does not imply that the component must be absolutely horizontal or vertical, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure or component must be completely horizontal, but can be slightly tilted.

[0036] In the description of the embodiments of this utility model, "a plurality of" means at least two.

[0037] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0038] Example

[0039] Please refer to the instruction manual attached. Figure 1 As shown, the instruction manual is attached. Figure 1 The image shows a shielding effectiveness line injection method testing fixture of this utility model. The fixture includes a base plate 1, which is a rectangular strip structure. Two sets of transmitting devices 2 are arranged along the left and right length of the top of the base plate 1. The transmitting devices are electrically connected to an external network analyzer via radio frequency cables. The two sets of transmitting devices 2 are symmetrically arranged left and right. For details, please refer to the appendix of the specification. Figure 3As shown, the transmitting device 2 consists of a fixed plate 21, a first N-head wall panel connector 221, a coaxial cable bracket 23, and a transmitter 24. The fixed plate 21 is fixedly installed on the base plate 1. To facilitate the adjustment of the left-right spacing between the two sets of transmitting devices 2, and to accommodate coupling length tests of conventional 0.5m and 0.3m cables, the top of the base plate 1 is provided with multiple vertical studs 11 along its length. Specifically, along the length of the base plate 1, at least two rows of stud groups are provided symmetrically. Each row of stud groups consists of three studs 11 arranged horizontally side by side. One stud 11 is close to one end of the base plate 1, and the other two studs 11 are spaced 0.3m apart from the first stud 11. The fixing plate 21 has connecting holes corresponding to the number and position of the longitudinally arranged studs 11. The connecting holes are fitted with the studs 11. After the fixing plate 21 is fitted onto the studs 11, it is fixed to the base plate 1 by nuts that are threaded into the studs 11, making it easy to assemble and disassemble. The first N-head wall panel connector 221 is set on the fixing plate 21 near the rear end via an N-head bracket 22. A coaxial cable 6 is connected to the first N-head wall panel connector 221. A coaxial cable bracket 23 corresponding to the front and rear ends of the first N-head wall panel connector 221 is set on the fixing plate 21 near the front end. For convenient support and connection of the coaxial cable 6, please refer to the appendix of the instruction manual. Figure 3 As shown, the coaxial cable bracket 23 has a coaxial clamping hole 231 at its top center, which is connected front to back. The coaxial clamping hole 231 corresponds to the first N-head wall panel connector 221. The coaxial cable 6 connected to the first N-head wall panel connector 221 passes through the coaxial clamping hole 231. In order to clamp and fix the coaxial cable 6 passing through the coaxial clamping hole 231, the top of the coaxial cable bracket 23 is provided with a cable cover 232 fixedly connected to it. The cable cover 232 clamps the coaxial cable 6 passing through the coaxial clamping hole 231. The transmitter 24 is fixedly installed on the fixed plate 21 on one side directly in front of the coaxial cable bracket 23. The two sets of transmitters 24 on the two sets of transmitter devices 2 are symmetrical from left to right. See the appendix of the instruction manual. Figure 4 and 5 As shown, the transmitter 24 includes an outer mounting frame 241, which is fixedly mounted on the mounting plate 21 by bolts. The outer mounting frame 241 has a top-opening, front-to-back connected assembly groove 2411 at its end center. The assembly groove 2411 has a rectangular structure, and a clamping replacement block 242 is embedded within it. The clamping replacement block 242 is fixedly connected to the outer mounting frame 241 by bolts. (See attached instruction manual). Figure 6As shown, the top center of the clamping replacement block 242 is provided with a clamping hole 2421 that connects the front and back. The clamping hole 2421 is used to guide the connection of the test cable 5. The clamping hole 2421 has a "U" shaped structure and a semi-circular structure at the bottom. In order to accommodate all sizes of cables, the diameter of the semi-circular bottom of the clamping hole 2421 is 4-20mm. That is, according to all diameter sizes of cables, a corresponding clamping replacement block 242 is designed for each size. The clamping hole 2421 on each clamping block 242 corresponds to the diameter of a cable. When testing cables of different diameters, the clamping replacement block 242 inside the outer fixing bracket 241 can be directly replaced. The entire transmitter 24 does not need to be replaced, reducing costs and making it more flexible and versatile. To restrict the test cable 5 passing through the clamping hole 2421, the top of the clamping replacement block 242 is provided with a partition 2431 fixedly connected to the top of the outer fixing frame 241. The center of the end of the partition 2431 is provided with a coaxial cable outlet hole 2441 that connects the front and rear ends. The coaxial cable outlet hole 2441 corresponds vertically to the clamping hole 2421 and is close to it. The coupling part of the end of the coaxial cable 6 is located within the coaxial cable outlet hole 2441. For securing the coaxial cable 6 passing through the coaxial cable outlet hole 2441, refer to the appendix of the instruction manual. Figure 5 As shown, the top of the partition 2431 is provided with a threaded hole that communicates vertically with the coaxial cable outlet hole 2441. A grounding screw 2432, threadedly engaged with the screw, is provided inside the threaded hole. The lower end of the grounding screw 2432 is located inside the coaxial cable outlet hole 2441. Rotating the grounding screw 2432 allows for vertical adjustment, thereby pressing the coaxial cable 6 inserted into the coaxial cable outlet hole 2441. A groove is provided near the front end of the top of the partition 2431. A silicone pressure block 244, which mates with the groove, is provided inside the groove. The bottom of the silicone pressure block 244 has a downward-opening, front-to-back pressure groove. The end of the pressure groove is semi-circular, corresponding vertically to the coaxial cable outlet hole 2441. It can be used with a coaxial cable 6 that passes through the coaxial cable outlet hole 2441, while the silicone pressure block 244 serves as a shield. A cable connection box 3 and a resistor shielding box 4 are provided on the front side of the base plate 1 near both sides. The cable connection box 3 and the resistor shielding box 4 are used for connecting the test cable 5. The cable connection box 3 and the resistor shielding box 4 are symmetrically positioned, and two sets of transmitters 24 are positioned between the corresponding cable connection box 3 and the resistor shielding box 4. To facilitate the fixing of the test cable 5, a connector 8 is provided at one end of each of the cable connection box 3 and the resistor shielding box 4 corresponding to the transmitter 24. The two connectors 8 are respectively mounted on the cable connection box 3 and the resistor shielding box 4 via two connecting blocks 9. For details, please refer to the appendix of the instruction manual. Figure 12As shown, the end center of the connecting block 9 is provided with a threaded connection hole 91 that connects the front and rear. The flange head 8 is screwed into the threaded connection hole 91. Of course, when testing connectors, a connector that facilitates connector connection can be installed on the connecting block 9, which has strong versatility; see the appendix of the instruction manual. Figures 7 to 9 As shown, the cable connection box 3 includes a three-dimensional rectangular connection box body 31 made of brass. It consists of a rectangular bottom plate and side plates fixedly arranged around the top of the bottom plate. The connection box body 31 has a top-opening connection cavity 311 for connecting the internal circuitry of the cable. A detachable top cover 30 is provided on the top of the connection box body 31. The front end of the connection box body 31 has a first guide hole 312 with internal and external communication. A connecting block 9 for connecting a flange connector 8 is fixed outside the first guide hole 312. The rear end of the cable connection box 3 has an internal and external communication assembly hole 313, in which a second N-head wall panel connector 32 is fixedly installed. A second N-head wall panel connector 32 is provided on the other end of the cable connection box 3 corresponding to its end flange connector 8. The second N-head wall panel connector 32 connects to a test cable 5 that passes through the connection cavity 311.

[0040] See the attached instruction manual. Figures 10 to 11 As shown, the resistor shielding box 4 includes a shielding box body 41 with a three-dimensional rectangular structure. The shielding box body 41 is made of brass and consists of a rectangular bottom plate and side plates that are connected and fixedly arranged around the top of the bottom plate. The shielding box body 41 has a shielding cavity 411 with a top opening inside. The shielding cavity 411 is used to install resistors. The top is provided with a detachable shielding box cover 40. The front end of the shielding box body 41 is provided with a second guide hole 412 that communicates with the inside and outside. A connecting block 9 for connecting a Grand head 8 is fixed outside the second guide hole 412.

[0041] See the attached instruction manual. Figure 2As shown, this fixture can perform coupling length tests of 0.5m and 0.3m; 0.3m is the minimum length allowed by the standard. When the test cable 5 is a high-voltage power supply cable for automobiles, the insulation layers at both ends and in the middle need to be stripped to expose the shielding layer connected to the transmitter 24. For the resistor side of the corresponding resistor shielding box 4, simply strip the outer insulation layer. Carefully wrap the opening of the shielding layer with insulating tape to prevent damage during subsequent operations. Then, place the cable and tape together into the matching resistor shielding box 4 and remove the tape. Next, install the corresponding matching resistor; low-inductance resistors such as surface mount resistors are recommended. The middle portion of the test cable 5 connected to the transmitter 24 also needs to have its insulation layer stripped. Then, prepare the injection wire 7. Copper foil or parallel wire is recommended for the injection wire 7. Attach the injection wire 7 to the test cable 5, and then solder the injection wire 7 to the core of the coaxial cable 6. The injection wire 7 should be tightly attached to the surface of the test cable 5 along the coupling section. The characteristic impedance of the injection circuit should be close to the output impedance of the transmitter 24 and the terminal load resistance R0. This matching can be achieved by finely adjusting the core wire width of the injection wire 7 to meet the testing requirements for the shielding effectiveness of the cable or connector.

[0042] This shielding effectiveness line injection test fixture is flexible and adjustable. The clamping replacement block in the transmitter can be flexibly replaced according to the diameter of the cable. It is flexible in use, and the spacing between the two sets of symmetrical transmitters can be flexibly adjusted. It can perform coupling length tests on 0.5m and 0.3m cables. Furthermore, the connecting blocks on the cable connection box and the resistor shielding box can be replaced according to the type of test piece to adapt to the connection of cables or connectors, making it highly versatile.

[0043] It should be emphasized that the above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A shielded effectiveness line injection method test fixture, characterized by: The device includes a base plate (1), which is a rectangular strip structure. Two sets of transmitting devices (2) are arranged on the top of the base plate (1) along its left and right length directions. The two sets of transmitting devices (2) are arranged symmetrically on the left and right sides. Each transmitting device (2) consists of a fixed plate (21), a first N-head wall panel connector (221), a coaxial cable bracket (23), and a transmitter (24). The fixed plate (21) is fixedly installed on the base plate (1). The first N-head wall panel connector (221) is set on the fixed plate (21) near the rear end through the N-head bracket (22). A coaxial cable bracket (23) corresponding to the front and rear of the first N-head wall panel connector (221) is set on the fixed plate (21) near the front end. The transmitter (24) is fixedly installed on the fixed plate (21) on the coaxial side. On one side directly in front of the cable bracket (23), the two sets of transmitters (24) on the two sets of transmitter devices (2) are symmetrically arranged on the left and right; the front of the base plate (1) near the two sides is provided with a cable connection box (3) and a resistor shield box (4), the cable connection box (3) and the resistor shield box (4) are corresponding to each other on the left and right, and the two sets of transmitters (24) are located between the corresponding cable connection box (3) and the resistor shield box (4); the cable connection box (3) and the resistor shield box (4) are each provided with a connector (8) at one end corresponding to the transmitter (24), and the two connectors (8) are respectively installed on the cable connection box (3) and the resistor shield box (4) through two connecting blocks (9). The other end of the cable connection box (3) corresponding to its end connector (8) is provided with a second N-head wall panel connector (32).

2. A shielded probe test tool according to claim 1, wherein: The top of the base plate (1) is provided with multiple vertical studs (11) along its length direction. The fixing plate (21) is provided with connecting holes that fit with the studs (11). After the fixing plate (21) is fitted onto the studs (11), it is fixed to the base plate (1) by nuts that fit with the studs (11).

3. The shielding effectiveness wire injection method testing fixture according to claim 1, characterized in that: The coaxial cable bracket (23) has a coaxial clamping hole (231) that is connected from front to back at the top center. The coaxial clamping hole (231) corresponds to the first N-head wall panel connector (221) from front to back. The coaxial cable bracket (23) has a cable cover (232) that is fixedly connected to the top of it.

4. The shielding effectiveness wire injection method testing fixture according to claim 1, characterized in that: The transmitter (24) includes an outer fixing frame (241). The outer fixing frame (241) has an assembly groove (2411) with a top opening and front-to-back connection at the center of its end. A clamping replacement block (242) is embedded in the assembly groove (2411). The top of the clamping replacement block (242) is provided with a partition (2431) that is fixedly connected to the top of the outer fixing frame (241). The center of the end of the partition (2431) is provided with a coaxial cable outlet hole (2441) that is front-to-back connection. A groove is provided at the top of the partition (2431) near the front end. A silicone pressure block (244) that cooperates with the groove is provided in the groove. The bottom of the silicone pressure block (244) is provided with a wire pressing groove with an opening facing downward and front-to-back connection. The end of the wire pressing groove has a semi-circular structure, which corresponds vertically to the coaxial cable outlet hole (2441).

5. The shielding effectiveness wire injection method testing fixture according to claim 4, characterized in that: The top center of the compression replacement block (242) is provided with a compression hole (2421) that is connected from front to back. The compression hole (2421) has a "U" shaped structure and a semi-circular structure at the bottom. The diameter of the semi-circle is 4-20mm.

6. The shielding effectiveness wire injection method testing fixture according to claim 4, characterized in that: The top of the partition (2431) is provided with a threaded hole that communicates vertically with the coaxial cable outlet hole (2441). A grounding screw (2432) that is threadedly engaged with the threaded hole is provided in the threaded hole. The lower end of the grounding screw (2432) is located inside the coaxial cable outlet hole (2441).

7. The shielding effectiveness wire injection method testing fixture according to claim 1, characterized in that: The cable connection box (3) includes a connection box body (31) with a three-dimensional rectangular structure. The connection box body (31) has a connection cavity (311) with a top opening inside and a detachable connection box cover (30) on the top. The front end of the connection box body (31) is provided with a first guide hole (312) that communicates with the inside and outside. A connecting block (9) for connecting the connector (8) is fixed outside the first guide hole (312). The rear end of the cable connection box (3) is provided with an assembly hole (313) that communicates with the inside and outside. The second N-head wall panel connector (32) is fixedly installed inside the second N-head wall panel connector (32).

8. The shielding effectiveness wire injection method testing fixture according to claim 1, characterized in that: The resistor shielding box (4) includes a shielding box body (41) with a three-dimensional rectangular structure. The shielding box body (41) has a shielding cavity (411) with a top opening inside and a detachable shielding box cover (40) on the top. The front end of the shielding box body (41) is provided with a second guide hole (412) that communicates with the inside and outside. A connecting block (9) for connecting the granite head (8) is fixed outside the second guide hole (412).

9. The shielding effectiveness wire injection method testing fixture according to claim 1, characterized in that: The end center of the connecting block (9) is provided with a threaded connecting hole (91) that connects the front and rear, and the granite head (8) is screwed into the threaded connecting hole (91).

Images