Shielding device for external cable in electromagnetic compatibility test

Abstract

The utility model relates to the technical field of electromagnetic compatibility tests, and discloses a shielding device for an external cable in an electromagnetic compatibility test. The utility model discloses a shielding device for an external cable in an electromagnetic compatibility test. The shielding device comprises a body, a grounding wire and two lock catches, wherein a containing cavity is formed in the body, the two ends of the containing cavity are open, the containing cavity can be arranged outside an external cable in a sleeving mode, the body comprises a shielding layer, and the shielding layer can prevent an electromagnetic field in the body from radiating to the outside of the body; one end of the grounding wire is connected with the shielding layer, and the other end is electrically connected with the ground; and the two lock catches are respectively arranged near the openings. According to the shielding device for the external cable in the electromagnetic compatibility test provided by the utility model, the external cable of the equipment to be tested can be accommodated in the accommodating cavity, and the shielding layer outside the accommodating cavity can prevent an electromagnetic field generated by the external cable from radiating to the outside of the body, so that electromagnetic waves are prevented from being emitted to an external environment; therefore, the test accuracy is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to electromagnetic compatibility test technical field especially relates to a shielding device for electromagnetic compatibility test in external cable. BACKGROUND

[0002] Electromagnetic compatibility refers to the mutual influence and interaction between various electronic devices, equipment and systems in electronic systems, and with the external electromagnetic environment. Different electronic devices and systems will produce electromagnetic waves, and these electromagnetic waves will interfere with other electronic devices and systems, causing abnormal device function or even damage. Therefore, in order to ensure that electronic devices and systems can operate normally in complex electromagnetic environment, electromagnetic compatibility test becomes crucial.

[0003] Commonly used test methods of electromagnetic compatibility include radiation emission test, radiation resistance test, conducted emission test and conducted resistance test. Radiation emission test is to evaluate the ability of the device in emitting electromagnetic radiation, and during the radiation emission test, the device under test is placed in an electromagnetic shielding chamber, and the intensity of the radiated electromagnetic wave is measured at each frequency under the working state of the device. In this test process, the conductive wire and signal line connected with the device under test will also emit electromagnetic waves to the external environment, thereby affecting the test accuracy.

[0004] Therefore, there is an urgent need for a shielding device for external cable in electromagnetic compatibility test to solve the above technical problems. UTILITY MODEL CONTENT

[0005] The utility model aims at providing a shielding device for external cable in electromagnetic compatibility test, which can solve the problem that the conductive wire and signal line connected with the device under test will also emit electromagnetic waves to the external environment during the radiation emission test, thereby affecting the test accuracy.

[0006] To achieve this purpose, the utility model adopts the following technical scheme: a shielding device for external cable in electromagnetic compatibility test, comprising,

[0007] The body is internally provided with a containing cavity, the containing cavity is open at both ends, the external cable passes through the opening into the containing cavity, the containing cavity can be sleeved on the outside of the external cable, and the body further comprises a shielding layer arranged outside the containing cavity, the shielding layer can prevent the electromagnetic field generated by the external cable in the containing cavity from radiating to the outside of the body;

[0008] The grounding wire is electrically connected with the ground at one end, and the diameter of the grounding wire gradually decreases from the end connected with the shielding layer to the end connected with the grounding wire;

[0009] Two locking devices are respectively located near the opening.

[0010] As an alternative, the shielding layer includes a first shielding layer disposed outside the receiving cavity and adjacent to the receiving cavity, the first shielding layer being made of a rigid insulator.

[0011] As an optional solution, the shielding layer includes a second shielding layer disposed outside the second shielding layer, and the material of the second shielding layer is metal.

[0012] As an alternative, the second shielding layer is a metal mesh.

[0013] As an alternative, the grounding wire is electrically connected to the second shielding layer.

[0014] As an alternative, the shielding layer includes a third shielding layer disposed outside the second shielding layer, and the material of the third shielding layer is an insulator.

[0015] As an alternative, the first shielding layer, the second shielding layer, and the third shielding layer are all hollow structures.

[0016] As an optional solution, the third shielding layer is provided with a copper foil shielding layer on the outside.

[0017] As an alternative, the locking device is a clamp.

[0018] As an alternative, the clamp includes a snap-fit ​​part, a locking part, and a wrench part connected to the locking part, wherein the snap-fit ​​part can be fitted onto the outside of the body.

[0019] The present invention has at least the following beneficial effects: The shielding device for external cables in electromagnetic compatibility testing provided in this application can accommodate the external cables of the device under test inside the accommodating cavity, and the shielding layer outside the accommodating cavity can prevent the electromagnetic field generated by the external cables inside the accommodating cavity from emitting electromagnetic waves into the external environment, thereby improving the accuracy of the test. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments of this utility model will be briefly introduced below.

[0021] Figure 1 A schematic diagram of the structure of a shielding device for an external cable in electromagnetic compatibility testing, provided by an embodiment of this utility model, at a first angle;

[0022] Figure 2A cross-sectional view of a shielding device for external cables used in electromagnetic compatibility testing, provided as an embodiment of this utility model;

[0023] Figure 3 for Figure 2 Enlarged view of part A in the image;

[0024] Figure 4 This is a schematic diagram of the clamp structure provided in an embodiment of the present utility model.

[0025] Figure label:

[0026] 1. Body; 11. Receiving cavity; 12. Opening; 13. First shielding layer; 14. Second shielding layer; 15. Third shielding layer; 16. Copper foil shielding layer; 17. Protective layer; 2. Grounding wire; 3. Locking device; 31. Snap-fit ​​part; 32. Locking part; 33. Wrench part. Detailed Implementation

[0027] In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit the scope of this utility model.

[0028] In existing technologies, during radiated emission testing, the device under test (DUT) is placed in an electromagnetically shielded room, and the intensity of its radiated electromagnetic waves is measured at each frequency while the device is in operation. During this testing process, the conductive wires and signal lines connected to the DUT also emit electromagnetic waves into the external environment, thus affecting the accuracy of the test.

[0029] Therefore, such as Figures 1 to 4 As shown, an embodiment of this utility model provides a shielding device for external cables in electromagnetic compatibility testing to solve the above-mentioned technical problems.

[0030] Specifically, a shielding device for external cables used in electromagnetic compatibility testing includes a body 1, a grounding wire 2, and two locking devices 3. The body 1 has an internal receiving cavity 11 with openings 12 at both ends. The external cable enters the receiving cavity 11 through one opening 12 and exits through the other opening 12, with a portion of the external cable located inside the receiving cavity 11. The receiving cavity 11 can be fitted over the external cable. Here, the external cable refers to a conductive wire, signal wire, or other wire connected to the device under test. The body 1 also includes a shielding layer disposed outside the receiving cavity 11, which can prevent electrical current generated by the external cable inside the receiving cavity 11. The magnetic field radiates outwards from the main body 1, thus preventing the emission of electromagnetic waves into the external environment. One end of the grounding wire 2 is connected to the shielding layer, and the other end of the grounding wire 2 is electrically connected to the ground. The wire diameter of the grounding wire 2 gradually decreases from the end connected to the shielding layer to the end connected to the grounding wire 2. This allows the electromagnetic signals generated by the external cable inside the receiving cavity 11 to be guided to the ground along the grounding wire 2, preventing the emission of electromagnetic waves into the external environment. Two locking devices 3 are respectively set near the opening 12. When the external cable is inserted into the receiving cavity 11, the two locking devices 3 are locked, preventing the electromagnetic waves generated by the external cable inside the receiving cavity 11 from radiating into the external environment through the opening 12.

[0031] In some embodiments, the shielding layer includes a first shielding layer 13, which is disposed outside the receiving cavity 11. The first shielding layer 13 is made of a rigid insulator. The first shielding layer 13 surrounds and forms the receiving cavity 11. In this way, the first shielding layer 13 can prevent electromagnetic waves generated by external cables inside the receiving cavity 11 from radiating to the outside of the receiving cavity 11, and can also facilitate the insertion of external cables into the receiving cavity 11.

[0032] In some embodiments, the shielding layer includes a second shielding layer 14, which is disposed outside the shielding layer 14, and the material of the second shielding layer 14 is metal.

[0033] In some embodiments, in order to save on the production cost of manufacturing the second shielding layer 14, the second shielding layer 14 is preferably a metal mesh.

[0034] In some embodiments, the grounding wire 2 is electrically connected to the second shielding layer 14, so that electromagnetic waves from the body 1 can be guided from the second shielding layer 14 to the ground.

[0035] In some embodiments, the shielding layer includes a third shielding layer 15, which is disposed outside the second shielding layer 14. The material of the third shielding layer 15 is an insulator. In this way, the third shielding layer 15 can not only prevent electromagnetic waves generated by the external cable inside the cavity 11 from radiating to the outside of the body 1, but also protect the second shielding layer 14.

[0036] In some embodiments, the first shielding layer 13, the second shielding layer 14, and the third shielding layer 15 are all hollow structures. The hollow structure can confine electromagnetic waves within the structure, thereby helping to prevent electromagnetic waves generated by external cables inside the cavity 11 from radiating into the external environment.

[0037] In some embodiments, a copper foil shielding layer 16 is provided outside the third shielding layer 15. The copper foil shielding layer 16 is used to prevent electromagnetic waves inside the body 1 from radiating to the outside of the body 1. In order to protect the copper foil shielding layer 16, a protective layer 17 can be provided outside the copper foil shielding layer 16. The protective layer 17 is preferably made of plastic.

[0038] In some embodiments, the locking device 3 is a clamp, which is existing technology and will not be described in detail here.

[0039] In some embodiments, the clamp includes a snap-fit ​​portion 31, a locking portion 32, and a wrench portion 33 connected to the locking portion 32. The snap-fit ​​portion 31 can be fitted onto the outside of the body 1 to lock the body 1 at the opening 12. The snap-fit ​​portion 31 is provided with a slot (not shown in the figure). The locking portion 32 is provided with a toggle member. The wrench portion 33 is connected to the toggle member. When it is necessary to adjust the circumferential length of the snap-fit ​​portion 31 along the body 1, the hand applies force to the wrench portion 31. The wrench portion 31 drives the toggle member to move. The toggle member moves the slot relative to the locking portion 32, thereby adjusting the circumferential length of the snap-fit ​​portion 31 along the body 1.

[0040] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A shielding device for external cables used in electromagnetic compatibility testing, characterized in that, include The body (1) has a cavity (11) inside, and the cavity (11) has openings (12) at both ends. The external cable passes through the openings (12) into the cavity (11). The cavity (11) can be fitted over the external cable. The body (1) also includes a shielding layer disposed outside the cavity (11). The shielding layer can prevent the electromagnetic field generated by the external cable in the cavity (11) from radiating to the outside of the body (1). Grounding wire (2), one end of which is connected to the shielding layer, and the other end of which is electrically connected to the ground, wherein the wire diameter of the grounding wire (2) gradually decreases from the end connected to the shielding layer to the end connected to the grounding wire (2); Two latches (3) are respectively located near the opening (12).

2. The shielding device for external cables in electromagnetic compatibility testing according to claim 1, characterized in that, The shielding layer includes a first shielding layer (13), which is disposed outside the receiving cavity (11) and adjacent to the receiving cavity (11). The material of the first shielding layer (13) is a rigid insulator.

3. A shielding device for external cables in electromagnetic compatibility testing according to claim 2, characterized in that, The shielding layer includes a second shielding layer (14), which is disposed outside the second shielding layer (14), and the material of the second shielding layer (14) is metal.

4. A shielding device for external cables in electromagnetic compatibility testing according to claim 3, characterized in that, The second shielding layer (14) is a metal mesh.

5. A shielding device for external cables in electromagnetic compatibility testing according to claim 3, characterized in that, The grounding wire (2) is electrically connected to the second shielding layer (14).

6. A shielding device for external cables in electromagnetic compatibility testing according to claim 3, characterized in that, The shielding layer includes a third shielding layer (15), which is disposed outside the second shielding layer (14), and the material of the third shielding layer (15) is an insulator.

7. A shielding device for external cables in electromagnetic compatibility testing according to any one of claims 2-6, characterized in that, The first shielding layer (13), the second shielding layer (14) and the third shielding layer (15) are all hollow structures.

8. A shielding device for external cables in electromagnetic compatibility testing according to claim 7, characterized in that, The third shielding layer (15) is provided with a copper foil shielding layer (16) on the outside.

9. A shielding device for external cables in electromagnetic compatibility testing according to any one of claims 1-6, characterized in that, The locking device (3) is a clamp.

10. A shielding device for external cables in electromagnetic compatibility testing according to claim 9, characterized in that, The clamp includes a snap-fit ​​part (31), a locking part (32), and a wrench part (33) connected to the locking part (32). The snap-fit ​​part (31) can be fitted onto the outside of the body (1).

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