A triaxial pipe-in-pipe shielding effectiveness test system device

Abstract

The application discloses a kind of three coaxial pipe-in-pipe shielding effectiveness test system device, including test tube, the test tube one end is provided with the injection end cap of signal input, the other end is provided with the test receiving head of signal output;The injection end cap is connected with the test tube screw thread, between being provided with locking clamp, the locking hole of being communicated at two ends is provided in the center of the locking clamp, the injection end cap end center is provided with the link hole corresponding with locking hole and mutually communicating, the link hole is coaxial with the center of locking hole and test tube.This three coaxial pipe-in-pipe shielding effectiveness test system device simple structure, the test use of adaptive cable and wire harness, detachable clamp block design facilitates different clamp opening size clamp block installation on test tube, facilitate the pipe-in-pipe clamping of different model size, strong universality, overcome the shortcoming of cable and wire harness test when disassembly laborious, product structure optimization, save the use cost of device, it is convenient to carry.

Description

Technical Field

[0001] This invention relates to a triaxial testing system, and more particularly to a triaxial tube-in-tube shielding effectiveness testing system device. Background Technology

[0002] Nowadays, new energy vehicles are becoming increasingly popular in people's daily lives, and high-voltage devices such as high-voltage cables are widely used in new energy vehicles. However, these high-voltage devices are susceptible to electromagnetic interference. If electromagnetic signals are not properly shielded, they will affect other devices in the vehicle. Therefore, OEMs usually make wiring harness shielding a mandatory test item to avoid interference from electromagnetic signals after the application of high-voltage devices.

[0003] Currently, the shielding effectiveness of wire harnesses is mostly tested using the triaxial method. The triaxial method is generally used to measure the surface transfer impedance and shielding attenuation of high-voltage cables. The triaxial test system mainly consists of a vector network analyzer, a test sleeve, a connecting cable, a test receiver, the cable shielding layer, the shielding copper tube, a matching connector, and characteristic impedance. One end of the high-voltage cable, i.e., the shielded cable under test, is connected to the connecting cable and installed together with the shielding copper tube. Then, it is inserted into the test sleeve. The high-frequency signal generated by the vector network analyzer (i.e., the signal generator) is transmitted to the shielded cable under test through the connecting cable. The other end of the shielded cable under test is connected to the impedance matching connector, which is connected to the characteristic impedance that matches the shielded cable under test.

[0004] This method measures the surface transfer impedance by injecting a fixed amount of current into the core wire of the shielded cable under test to test the coupling voltage between the shielding layer and the test fixture, or by injecting a fixed amount of current into the loop formed by the outer surface of the shielding layer of the shielded cable under test and the test fixture to test the coupling voltage between the shielding layer and the cable core wire, thereby obtaining the shielding efficiency of the cable.

[0005] In a triaxial testing system, different types of high-voltage cables need to be matched with different signal connection cables, and the connection cables need to be matched with shielded copper tubes of corresponding sizes. Therefore, the shielded copper tubes come in various sizes and need to be adapted to test sleeves of corresponding sizes, which makes the testing system relatively expensive to use and inconvenient to carry. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a versatile and secure triaxial tube-in-tube shielding effectiveness testing system device.

[0007] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0008] A three-coaxial tube-in-tube shielding effectiveness testing system device includes a test tube. One end of the test tube is provided with an injection end cap for convenient signal input, and the other end is provided with a test receiver head for convenient signal output. The injection end cap is threadedly connected to the test tube, and a locking clamp is provided between them. The locking clamp has a locking hole with two communicating ends at its center. The injection end cap has a connecting hole at its center that corresponds to and communicates with the locking hole. The connecting hole is coaxial with the center of the locking hole and the center of the test tube.

[0009] Furthermore, a tube-in-tube is provided in the locking hole at the center of the locking clamp block, with one end of the tube-in-tube located inside the test tube and the other end located outside the injection end cap; an annular pressure block is provided between the injection end cap and the locking clamp block for the locking clamp block to clamp the outside of the tube-in-tube.

[0010] Furthermore, the locking clamping block is composed of two semi-circular clamping blocks. The clamping block has a semi-circular groove in its center. The two semi-circular grooves of the two clamping blocks that are joined together form a locking hole. The clamping block has a conical protrusion on one side. The conical protrusions on the sides of the two clamping blocks that are joined together form a conical annular locking part. The annular pressure block has a conical locking hole that is connected from left to right in its center. The annular pressure block is fitted onto the outside of the annular locking part through its central conical locking hole.

[0011] Furthermore, the outer center of the test receiver head is provided with an SMA straight-through head that is threadedly connected thereto; the inner center is provided with an N-type head that is connected to the SMA straight-through head, and the other end of the N-type head corresponding to the SMA straight-through head is provided with a resistor tube that is threadedly connected thereto.

[0012] Furthermore, the N-type head is provided with an insulating support ring that fits into it.

[0013] Furthermore, the end of the tube-in-tube located inside the test tube is provided with a threaded clamping block tube that is threadedly connected thereto, and the other end of the threaded clamping block tube is provided with a straight end that is threadedly connected thereto.

[0014] Furthermore, a centering clamp is provided inside the test tube, and the centering clamp is provided with a concave U-shaped limiting groove.

[0015] Furthermore, the test receiver head and the test tube are fixedly connected together by a clamp.

[0016] Furthermore, a support base is provided at the bottom of the test tube.

[0017] Compared with the prior art, the advantages of this invention are: the three-coaxial tube-in-tube shielding effectiveness testing system has a simple structure, is suitable for testing cables and wire harnesses, and the detachable clamp design makes it easy to install clamps of different clamp sizes on the test tube, which is convenient to fit different models and sizes of tube-in-tube clamps. It has strong versatility, overcomes the disadvantage of laborious disassembly and assembly during cable and wire harness testing, optimizes the product structure, saves the cost of using the device, and is easy to carry. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention 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.

[0019] Figure 1 This is a schematic diagram of the axial structure of the signal injection end of a three-coaxial tube-in-tube shielding effectiveness testing system device according to the present invention;

[0020] Figure 2 This is a schematic diagram of the axial structure of the signal receiving end of a shielding effectiveness testing system device using the three-coaxial tube-in-tube method according to the present invention;

[0021] Figure 3 This is a top view schematic diagram of the shielding effectiveness testing system device of the three coaxial tube-in-tube method according to the present invention;

[0022] Figure 4 yes Figure 3 Structural cross-sectional view of AA;

[0023] Figure 5 This is a cross-sectional view of the side structure of the test tube in the shielding effectiveness testing system of the three coaxial tube-in-tube method of the present invention;

[0024] Figure 6 This is a schematic diagram of the assembly structure of the inner tube and locking clamp of the inner tube of the three coaxial tube-in-in-tube shielding effectiveness testing system device of the present invention;

[0025] Figure 7 This is a schematic diagram of the threaded clamping block tube structure in a shielding effectiveness testing system device for the three coaxial tube-in-tube method of the present invention;

[0026] Figure 8 This is a schematic diagram of the disassembled structure of the locking clamp and the annular pressure block in the shielding effectiveness testing system device of the three coaxial tube-in-tube method of the present invention;

[0027] Figure 9 This is a schematic diagram of the internal structure of the test receiver head in a three-coaxial tube-in-tube shielding effectiveness testing system device of the present invention;

[0028] Figure 10 This is a schematic diagram of the support base structure in the shielding effectiveness testing system device of the three coaxial tube-in-tube method of the present invention;

[0029] Figure 11 This is a schematic diagram of the centering tube clamp structure in a shielding effectiveness testing system device for the three coaxial tube-in-tube method of the present invention.

[0030] In the diagram: 1. Test tube; 2. Tube-in-tube; 21. Threaded clamping block tube; 211. Straight end; 3. Injection end cap; 30. Connecting hole; 31. Locking clamp; 311. Conical protrusion; 312. Locking hole; 313. Slot; 32. Annular pressure block; 321. Conical locking hole; 4. Test receiver head; 41. Resistance tube; 42. N-type head; 43. Insulating support ring; 44. SMA straight end; 5. Clamp; 6. Support base; 7. Centering tube clamp; 71. Limiting groove. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the 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 invention without inventive effort are within the scope of protection of the 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 invention, it should be noted that if terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," or "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 is in use, they are only for the convenience of describing the 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 invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0033] 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.

[0034] In the description of the embodiments of the present invention, "multiple" means at least two.

[0035] In the description of the embodiments of the present invention, 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 the present invention according to the specific circumstances.

[0036] Example

[0037] Please refer to the instruction manual attached. Figures 1 to 3 As shown, the instruction manual is attached. Figures 1 to 3 The diagram illustrates a specific embodiment of a three-coaxial tube-in-tube shielding effectiveness testing system device according to the present invention. This system is used for testing the transfer impedance and shielding attenuation of high-speed communication cables, connectors, and wire harnesses. The three-coaxial tube-in-tube shielding effectiveness testing system device in this embodiment includes a test tube 1, which is made of aluminum alloy and is a long tube with a circular end face. A cavity extending through both ends is provided at the center of the test tube 1 along its length. To ensure stability during testing, a support base 6 is provided at the bottom of the test tube 1. (See attached specification). Figure 4As shown, the support base 6 has a trapezoidal structure on its side and a groove on its top that mates with the test tube 1. In this embodiment, the support base 6 has at least two sets, symmetrically arranged at the bottom of the test tube 1 near both ends. One end of the test tube 1 is provided with an injection end cap 3 for convenient signal input. The injection end cap 3 is threadedly connected to the test tube 1. Specifically, the injection end cap 3 has an internal threaded connection hole corresponding to the end of the test tube 1, and the outer side of the end of the test tube 1 used to connect to the injection end cap 3 has an external thread that mates with the internal threaded connection hole on the injection end cap 3. The injection end cap 3 is screwed onto the external thread at the end of the test tube 1. To facilitate cable clamping, a locking clamp 31 is provided between the injection end cap 3 and the test tube 1. The locking clamp 31 has a locking hole 312 with both ends communicating in the center. To facilitate cable or wire harness insertion, the injection end cap 3 has a connecting hole 30 at its center, which corresponds to and communicates with the locking hole 312. The connecting hole 30 is coaxial with the locking hole 312 and the inner cavity center of the test tube 1. It should be noted that in this embodiment, the diameter of the connecting hole 30 is larger than the diameter of the locking hole 312. When testing the cable, the locking hole 312 at the center of the locking clamp 31 clamps the outer shielding layer of the cable. In order to limit the axial position of the locking clamp 31 in the test tube 1, a concave centering hole is provided at the opening of one end of the test tube 1 used to connect the injection end cap 3. The locking clamp 31 is embedded in the centering hole. After the cable is inserted into the locking hole 312, the injection end cap 3 is tightened to the end of the test tube 1 to fix the locking clamp 31 and clamp the cable in the center.

[0038] For ease of wiring harness testing, please refer to the appendix of the instruction manual. Figure 4 As shown, a tube-in-tube 2 is installed in the locking hole 312 at the center of the locking clamp 31, and the tube-in-tube 2 is a copper tube. One end of the tube-in-tube 2 is located inside the test tube 1, and the other end is located outside the injection end cap 3. A connecting cable is threaded through the tube-in-tube 2. For convenient wiring harness connection, please refer to the appendix of the instruction manual. Figure 4 and 7 As shown, the end of the tube-in-tube 2 located inside the test tube 1 is provided with a threaded clamping block tube 21 that is threadedly connected to it. A straight connector 211, threadedly connected to the other end of the threaded clamping block tube 21 corresponding to the tube-in-tube 2, is provided with a straight connector 211 that is threadedly connected to it. One end of the straight connector 211 is connected to the connecting cable, and the other end is connected to the end connector of the wire harness passing through the test tube 1. To cooperate with the locking clamp 31 to clamp and fix the tube-in-tube 2 through the injection end cap 3, please refer to the appendix of the instruction manual. Figure 5 and 6 As shown, an annular pressure block 32 for clamping the outside of the tube-in-tube 2 is provided between the injection end cap 3 and the locking clamp block 31; to adapt to the clamping and fixing of tube-in-tube 2 of different diameters in the test tube 1, please refer to the appendix of the instruction manual. Figure 8As shown, the locking clamp 31 consists of two semi-circular clamping blocks. Each clamping block has a semi-circular groove 313 at its center, which can be engaged with the outside of the tube-in-tube 2 or cable. The two centrally symmetrical semi-circular grooves 313 of the two mating clamping blocks form a locking hole 312. To adjust the tightness of the locking clamp 31 by adjusting the position of the injection end cap 3 at the end of the test tube 1, one side of each clamping block has an outwardly protruding conical protrusion 311 along the contour of its groove 313. The two mating clamping blocks have conical protrusions 311 on their sides forming a conical annular locking part. The annular pressure block 32 has a centrally connected... The conical locking hole 321 is used to fit the annular pressure block 32 outside the annular locking part. When the axial position of the locking clamping block 31 remains unchanged, the annular pressure block 32 moves towards the locking clamping block 31. Under the interaction of the conical locking hole 321 and the annular locking part, the locking hole 312 tightens towards the center, which can clamp the tube-in-tube 2 inserted therein. The movement of the annular pressure block 32 towards the locking clamping block 31 is achieved by screwing the injection end cap 3 onto the end of the test tube 1. When the injection end cap 3 is loosened from the end of the test tube 1, the corresponding annular pressure block 32 loosens its constraint on the locking clamping block 31, which makes it easier for the locking clamping block 31 to loosen and clamp the tube-in-tube 2.

[0039] For convenient signal output, please refer to the appendix of the instruction manual. Figures 1 to 3 As shown, a test receiver 4 for convenient signal output is provided on the test tube 1 at the other end opposite to the injection end cap 3. The test receiver 4 is fixedly connected to the test tube 1 by a clamp 5, which facilitates easy assembly and disassembly. (See attached instruction manual.) Figure 4 and 9 As shown, the outer center of the test receiver head 4 is provided with an SMA straight-through head 44 that is threadedly connected to it, and the inner center is provided with an N-type head 42 that is connected to the SMA straight-through head 44. A resistor tube 41 is provided on the N-type head 42 corresponding to the other end of the SMA straight-through head 44 and threadedly connected to it. A terminating matching resistor for the connecting cable or wire harness is installed inside the resistor tube 41. To ensure the position of the N-type head 42 in the test tube 1 and to ensure coaxiality, please refer to the appendix of the instruction manual. Figure 4 As shown, the N-type head 42 is provided with an insulating support ring 43 that fits into it, and the insulating support ring 43 is vertically embedded in the inner cavity of the test tube.

[0040] To provide support for the cables or wire harnesses running through test tube 1, please refer to the appendix of the instruction manual. Figure 4As shown, a centering clamp 7 is provided inside the test tube 1. The centering clamp 7 is made of insulating material and is vertically embedded in the inner cavity of the test tube 1. The number of centering clamps 7 inside the test tube 1 can be increased or decreased according to the actual length of the test tube 1 to ensure that the centering clamps 7 can support the cable or wire harness. To facilitate the support and constraint of the cable or wire harness and ensure its position in the test tube 1, please refer to the appendix of the instruction manual. Figure 11 As shown, the center tube clamp 7 is provided with a concave U-shaped limiting groove 71, and the cable or wire harness is located in the limiting groove 71.

[0041] Specifically,

[0042] Cable testing: The cable is threaded through the test tube 1. In this embodiment, the test tube 1 has an inner diameter of 40mm. One end of the cable is connected to the signal output terminal of the vector network analyzer for signal injection. The other end passes through the locking hole 312 in the center of the locking clamp 31 and is connected to the terminal matching resistor in the resistor tube 41 of the test receiver head 4. The injection end cap 3 is screwed onto the test tube 1. The locking clamp 31 is clamped by the restriction of the injection end cap 3 on the locking clamp 31. It should be noted that the insulation layer on the cable corresponding to the locking hole 312 is stripped to expose the cable. The shielding layer is brought into contact with the locking clamp 31. The cable in the test tube 1 is supported by the centering clamp 7 embedded inside to ensure its centering. The SMA straight-through head 44 on the test receiver head 4 is connected to the signal input terminal of the vector network analyzer via a coaxial cable. The vector network analyzer injects a signal into the cable through its output terminal, and then transmits the signal to the signal input terminal of the vector network analyzer through the test receiver head to receive the signal and obtain the S21 parameters of the network analyzer. Then, the transfer impedance and shielding attenuation value of the cable are calculated to determine the shielding effectiveness of the cable.

[0043] Wire harness testing: In this embodiment of the invention, the test tube 1 has an inner diameter of 40mm. A tube-in-tube 2 is installed in the locking hole 312 of the locking clamp 31. A connecting cable is installed inside the tube-in-tube 2. One end of the connecting cable is connected to the straight connector 211 at the end of the tube-in-tube 2, and the other end is connected to the signal output terminal of the vector network analyzer. The wire harness under test is installed inside the test tube 1. One end of the wire harness under test is connected to the straight connector 211 at the end of the tube-in-tube 2, and the connection to the connecting cable is achieved through the straight connector 211. The other end is connected to the terminating matching resistor in the resistor tube 41 in the test receiver head 4. The SMA straight connector 44 on the test receiver head 4 is connected to the signal input terminal of the vector network analyzer through a coaxial cable. The tube 2 is inserted into the locking hole 312 of the locking clamp 31. The injection end cap 3 at the end of the test tube 1 is tightened. During the tightening process of the injection end cap 3, the annular pressure block 32 drives the locking clamp 31 to clamp and fix the tube 2 in the tube-in-tube direction towards the center, locking the tube-in-tube 2. The wire harness in the test tube 1 is supported by the centering tube clamp 7 embedded inside to ensure its centering. The vector network analyzer injects the signal into the core of the connecting cable through the output end and transmits the signal to the wire harness under test. Then, the signal is transmitted to the signal input end of the vector network analyzer through the test receiver head 4 to receive the signal and obtain the S21 parameters of the network analyzer. Then, the transfer impedance and shielding attenuation value of the wire harness are calculated to determine the shielding effectiveness of the wire harness.

[0044] This three-coaxial tube-in-tube shielding effectiveness testing system has a simple structure and is suitable for testing cables and wire harnesses. The detachable clamp design makes it easy to install clamps of different clamp sizes on the test tube, and it is convenient to use with tube-in-tube clamps of different models and sizes. It has strong versatility and overcomes the disadvantage of laborious disassembly and assembly during cable and wire harness testing. The product structure is optimized, saving the cost of using the device and making it easy to carry.

[0045] It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A shielding effectiveness testing system device using a three-coaxial tube-in-tube method, comprising a test tube (1), characterized in that: The test tube (1) is provided with an injection end cap (3) for convenient signal input at one end and a test receiver head (4) for convenient signal output at the other end; the injection end cap (3) is threadedly connected to the test tube (1) and a locking clamp (31) is provided between them; the locking clamp (31) is provided with a locking hole (312) with both ends connected at the center; the injection end cap (3) is provided with a connecting hole (30) at the center of its end that corresponds to and is connected to the locking hole (312); the connecting hole (30) is coaxial with the center of the locking hole (312) and the center of the test tube (1).

2. The shielding effectiveness testing system device of the three-coaxial tube-in-tube method according to claim 1, characterized in that: The locking hole (312) in the center of the locking clamp (31) is provided with a tube-in-tube (2) that is inserted and matched with it. One end of the tube-in-tube (2) is located inside the test tube (1), and the other end is located outside the injection end cap (3). An annular pressure block (32) for clamping the tube-in-tube (2) outside the tube-in-tube (2) is provided between the injection end cap (3) and the locking clamp (31).

3. The shielding effectiveness testing system device for the three-coaxial tube-in-tube method according to claim 2, characterized in that: The locking block (31) is composed of two semi-circular clamping blocks. The center of the clamping block is provided with a semi-circular groove (313). The two semi-circular grooves (313) of the two clamping blocks are symmetrically arranged to form a locking hole (312). A conical protrusion (311) is provided on one side of the clamping block. The conical protrusion (311) on the side of the two clamping blocks are formed to form a conical annular locking part. The center of the annular pressure block (32) is provided with a conical hole (321) that is connected from left to right. The annular pressure block (32) is fitted on the outside of the annular locking part through its central conical hole (321).

4. The shielding effectiveness testing system device of the three coaxial tube-in-tube method according to claim 1, characterized in that: The test receiver (4) has an SMA straight-through head (44) threadedly connected to its outer center; an N-type head (42) connected to the SMA straight-through head (44) is provided at the inner center, and a resistor tube (41) threadedly connected to the other end of the N-type head (42) corresponding to the SMA straight-through head (44) is provided on its other end.

5. The shielding effectiveness testing system device for the three-coaxial tube-in-tube method according to claim 4, characterized in that: The N-type head (42) is provided with an insulating support ring (43) that fits into it.

6. The shielding effectiveness testing system device of the three coaxial tube-in-tube method according to claim 1, characterized in that: The end of the tube-in-tube (2) located inside the test tube (1) is provided with a threaded clamping block tube (21) that is threadedly connected to it. The other end of the threaded clamping block tube (21) is provided with a straight end (211) that is threadedly connected to it.

7. The shielding effectiveness testing system device of the three coaxial tube-in-tube method according to claim 1, characterized in that: The test tube (1) is provided with a centering tube clamp (7), and the centering tube clamp (7) is provided with a concave U-shaped limiting groove (71).

8. The shielding effectiveness testing system device of the three coaxial tube-in-tube method according to claim 1, characterized in that: The test receiver head (4) and the test tube (1) are fixedly connected together by a clamp (5).

9. The shielding effectiveness testing system device of the three coaxial tube-in-tube method according to claim 1, characterized in that: The test tube (1) is provided with a support base (6) at the bottom.

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