Shield structure

Abstract

To provide a shield structure capable of ensuring the shielding effect of a power cable while reducing the number of components and saving space.SOLUTION: A shield structure includes: a housing formed from conductive material; a power cable that extends from the outside of the housing to the inside of the housing through a through hole formed in the housing, and is connected to a power supply device; and a ring member that is formed of a conductive material with elasticity and is located between the housing and the power cable in the through hole. The housing includes a first housing component and a second housing component that are assembled. The through hole is formed straddling the boundary between the first and second housing components. The ring member is fixed to the outer surface of the power cable in contact with the shield layer that the power cable has, and the through hole is sandwiched between the inner circumferential surface of the first housing component and the inner circumferential surface of the second housing component. At least one of the first and second housing components has at least one protrusion that protrudes toward the ring member on the inner surface of the through hole.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The technology disclosed in this specification relates to a shielding structure for a power cable. [Background technology]

[0002] A power cable is inserted into a housing that houses a power supply device such as a power supply circuit to supply power from the outside of the housing, and the power cable is connected to the power supply device inside the housing.

[0003] According to Patent Document 1, an electric cable is inserted into a through-hole in a side wall of a terminal block housing made of a conductive material, and the terminal of the electric cable is connected to a terminal block provided inside the terminal block housing. A conductive shield support part is provided inside the terminal block housing. Inside the terminal block housing, the exposed part of the shield of the electric cable is sandwiched between the shield support part and a shield pressing member, and the shield pressing member is fixed by attaching it to the shield support part with a screw. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-114494 A Summary of the Invention [Problem to be solved by the invention]

[0005] In order to properly ensure the shielding effect of a power cable, conventionally, the number of parts and the required space have been problems. In Patent Document 1, various parts such as a shield support, a shield pressing member, and screws are required to connect the shield of the electric cable to the housing, and space is also required within the housing to accommodate these parts. This specification presents a technology useful for solving these problems. [Means for solving the problem]

[0006] This specification discloses a shielding structure. The shielding structure includes a housing made of a conductive material that houses a power supply device, a power cable that extends from the outside of the housing to the inside of the housing through a through hole formed in the housing and is connected to the power supply device, and a ring member made of a resilient conductive material that is interposed between the housing and the power cable at the through hole. The housing includes a first housing part and a second housing part that are assembled to each other, and the through hole is formed across the boundary between the first housing part and the second housing part. The ring member is fixed to the outer surface of the power cable while contacting a shielding layer of the power cable and is sandwiched between the inner surfaces of the first housing part and the second housing part at the through hole, and at least one of the first housing part and the second housing part has at least one protrusion on the inner surface of the through hole that protrudes toward the ring member.

[0007] According to the above configuration, the ring member is fixed to the outer peripheral surface of the power cable while contacting the shielding layer of the power cable, and is sandwiched between the inner peripheral surfaces of the first housing part and the second housing part in the through hole, and is also in contact with the protrusion. In other words, electrical continuity between the shielding layer of the power cable and the housing is ensured via the elastic ring member. This achieves an appropriate shielding effect for the power cable while reducing the number of parts and saving space compared to conventional configurations. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing a simplified configuration including a power cable and a housing according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing the relationship between the power cable, the ring member, and the housing from the same perspective as FIG. 1. [Figure 3] FIG. [Figure 4]10 is a diagram showing the relationship between the power cable, the ring member, and the housing from a perspective facing the side surface of the housing from outside the housing. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present embodiment will be described with reference to the drawings. Each drawing is merely an example, and the present embodiment is not limited to the contents shown in the drawings. Furthermore, since each drawing is an example, the shapes shown in the drawings may not necessarily be accurate, and some parts may be omitted.

[0010] Fig. 1 shows a simplified configuration including a power cable 10 and a housing 20 according to this embodiment. Fig. 1 shows a cross section of the power cable 10 and the housing 20. The housing 20 is made of a conductive material such as metal, and houses a power supply device 30 inside. The power cable 10 passes through a through-hole 23 formed in the housing 20, extends from the outside of the housing 20 to the inside of the housing 20, and is connected to the power supply device 30.

[0011] The power supply device 30 includes, for example, a power supply circuit mounted on a substrate. The power supply circuit includes, for example, an AC / DC converter that converts AC power to DC, a DC / DC converter that converts the DC level to a required level, and the like. AC power is input to the power supply device 30 through a power cable 10. The device or facility in which the power cable 10 and the housing 20 are disposed is not particularly limited. As an example, the power cable 10 and the housing 20 are disposed inside a vehicle. For example, AC power supplied from outside the vehicle through a charging cable connected to the vehicle flows to the power cable 10 via a specified connector. The AC power supplied from the power cable 10 to the power supply device 30 is then converted to DC via the power supply device 30 and used to charge a battery installed in the vehicle.

[0012] The housing 20 includes a first housing part 21 and a second housing part 22 that are assembled together. That is, the first housing part 21 and the second housing part 22 are assembled together with their open surfaces facing each other, thereby forming a space inside and constituting at least a part of the housing 20.

[0013] The through hole 23 is a hole of a size that allows the power cable 10 to pass through, and is formed on a certain side surface of the housing 20. The side surface on which the through hole 23 is formed includes a first side surface 21a that is part of the first housing component 21 and a second side surface 22a that is part of the second housing component 22. The through hole 23 is formed across the boundary between the first housing component 21 and the second housing component 22. In other words, if the through hole 23 is, for example, a circular hole, the through hole 23 is formed when a semicircular notch formed in the first side surface 21a of the first housing component 21 and a semicircular notch formed in the second side surface 22a of the second housing component 22 face each other across the boundary between the first housing component 21 and the second housing component 22.

[0014] As will be described below, a ring member 40 is interposed between the housing 20 and the power cable 10 in the through hole 23. The ring member 40 is made of an elastic conductive material, such as a metal plate. The shield structure 50 according to this embodiment includes the power cable 10, the ring member 40, and the housing 20.

[0015] FIG. 2 shows the relationship between the power cable 10, the ring member 40, and the housing 20 in a cross-sectional view taken from the same perspective as FIG. 1. The power cable 10 has a substantially circular cross section perpendicular to the direction in which the cable extends (see FIG. 4), and includes a core wire 11 as a conductor, an insulating layer 12 that covers the periphery of the core wire 11, a shielding layer 13 that covers the periphery of the insulating layer 12, and an outer cover (sheath) 14 that covers the periphery of the shielding layer 13. The power cable 10 may include multiple core wires 11. The core wire 11 is electrically connected to the power supply device 30 within the housing 20. The shielding layer 13 is a layer made of metal, and is formed, for example, of a braided wire made of woven metal wires.

[0016] 3 shows a perspective view of the ring member 40. The ring member 40 is configured by integrating a first ring portion 41, a second ring portion 42, and a connecting ring portion 43, and is cylindrical overall. The diameter of the second ring portion 42 is larger than the diameter of the first ring portion 41. The connecting ring portion 43 extends between the first ring portion 41 and the second ring portion 42, which have different diameters, and connects the first ring portion 41 and the second ring portion 42.

[0017] The ring member 40 is fixed to the outer peripheral surface of the power cable 10 while contacting the shield layer 13 of the power cable 10, and is sandwiched between the inner peripheral surface 23a (first inner peripheral surface 23a) of the first housing component 21 and the inner peripheral surface 23b (second inner peripheral surface 23b) of the second housing component 22 in the through hole 23. As described above, the semicircular notch formed in the first side surface 21a of the first housing component 21 results in the first inner peripheral surface 23a being curved in a semicircular shape. Similarly, the semicircular notch formed in the second side surface 22a of the second housing component 22 results in the second inner peripheral surface 23b being curved in a semicircular shape. In other words, the first inner peripheral surface 23a and the second inner peripheral surface 23b define the extent of the through hole 23.

[0018] 2, at the end of power cable 10 located inside housing 20, outer sheath 14 is removed to expose shielding layer 13. First ring portion 41 of ring member 40 is in contact with this exposed shielding layer 13 and is crimped and fixed to power cable 10 from the outer periphery of power cable 10. Meanwhile, second ring portion 42 of ring member 40 is sandwiched between first inner periphery 23a and second inner periphery 23b with its outer periphery in contact with first inner periphery 23a and second inner periphery 23b.

[0019] Because the ring member 40 is elastic, the ring member 40 and the first and second inner circumferential surfaces 23a, 23b of the through hole 23 press against each other. The shape of the ring member 40 is not limited to the example shown in Figure 3. For example, if the outer diameter of the power cable 10 and the inner diameter of the through hole 23 are approximately the same, there may be no or almost no difference in diameter between the first ring portion 41 and the second ring portion 42.

[0020] Furthermore, in this embodiment, at least one of the first housing part 21 and the second housing part 22 has at least one protrusion 24 protruding toward the ring member 40 on the inner circumferential surfaces 23a, 23b of the through-hole 23.

[0021] FIG. 4 shows the relationship between the power cable 10, the ring member 40, and the housing 20 from a perspective facing the first side surface 21a and the second side surface 22a from the outside of the housing 20. According to the example in FIG. 4, multiple protrusions 24 are formed on the second inner circumferential surface 23b of the second housing component 22. The protrusions 24 may be understood to be made of the same material as the housing component that has the protrusions 24. The protrusions 24 press against the second ring portion 42 of the ring member 40. Therefore, the second ring portion 42, pressed by the protrusions 24, presses against the first inner circumferential surface 23a. One or more protrusions 24 may be formed on the first inner circumferential surface 23a instead of the second inner circumferential surface 23b. One or more protrusions 24 may be formed on each of the first inner circumferential surface 23a and the second inner circumferential surface 23b.

[0022] As described above, according to the present embodiment, the shield structure 50 includes a housing 20 made of a conductive material and accommodating a power supply device 30 therein; a power cable 10 extending from the outside of the housing 20 to the inside of the housing 20 through a through hole 23 formed in the housing 20 and connected to the power supply device 30; and a ring member 40 made of a resilient conductive material and interposed between the housing 20 and the power cable 10 at the through hole 23. The housing 20 includes a first housing part 21 and a second housing part 22 that are assembled to each other. The through hole 23 is formed across the boundary between the first housing part 21 and the second housing part 22. The ring member 40 is fixed to the outer circumferential surface of the power cable 10 in contact with the shield layer 13 of the power cable 10, and is sandwiched at the through hole 23 between the inner circumferential surface 23 a of the first housing part 21 and the inner circumferential surface 23 b of the second housing part 22. Furthermore, at least one of the first housing part 21 and the second housing part 22 has at least one protrusion 24 protruding toward the ring member 40 on the inner circumferential surfaces 23a, 23b of the through-hole 23.

[0023] According to the above configuration, the ring member 40 is fixed to the outer peripheral surface of the power cable 10 while contacting the shielding layer 13 of the power cable 10, and is sandwiched between the first inner peripheral surface 23a of the first housing part 21 and the second inner peripheral surface 23b of the second housing part 22 in the through hole 23 of the housing 20, and is also in contact with the protrusion 24. In other words, electrical continuity between the shielding layer 13 of the power cable 10 and the housing 20 is ensured via a single component, the elastic ring member 40. No space is required within the housing 20 to ensure electrical continuity between the shielding layer 13 and the housing 20. In other words, according to this embodiment, the number of components is reduced and space is saved compared to the prior art, while still ensuring an appropriate shielding effect for the power cable 10.

[0024] Furthermore, the housing 20 is made of, for example, metal, and the dimensions and shape of the through hole 23 are made to match the outer shape of the power cable 10. However, the dimensions and shape of such through hole 23 are not necessarily reproduced with high accuracy relative to the ideal dimensions and shape during the process of manufacturing the housing 20. According to this embodiment, the convex portions 24 are formed on the inner circumferential surfaces 23a, 23b of the through hole 23, and therefore, even if the reproduction accuracy of the dimensions and shape of the through hole 23 is not very high, contact between the through hole 23 and the ring member 40 is ensured via the convex portions 24.

[0025] Although specific examples of the technology disclosed in this specification have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings simultaneously achieves multiple objectives, and achieving one of those objectives itself has technical utility. [Explanation of symbols]

[0026] 10: power cable, 13: shielding layer, 20: housing, 21: first housing part, 21a: first side surface, 22: second housing part, 22a: second side surface, 23: through hole, 23a: first inner peripheral surface, 23b: second inner peripheral surface, 24: protrusion, 30: power supply device, 40: ring member, 50: shielding structure

Claims

[Claim 1] A shielding structure, a housing made of a conductive material that houses a power supply device therein; a power cable that passes through a through hole formed in the housing, extends from the outside of the housing to the inside of the housing, and is connected to the power supply device; a ring member that is interposed between the housing and the power cable in the through hole and is made of an elastic conductive material, the housing includes a first housing part and a second housing part that are assembled to each other; the through-hole is formed across the boundary between the first housing part and the second housing part, the ring member is fixed to an outer circumferential surface of the power cable in a state of contact with a shielding layer of the power cable, and is sandwiched between an inner circumferential surface of the first housing part and an inner circumferential surface of the second housing part in the through hole, At least one of the first housing part and the second housing part has at least one protrusion on the inner circumferential surface of the through hole that protrudes toward the ring member.

Images