Shield wire connection structure

Abstract

A shield wire connection structure (10) connects a shield wire (11) and a metal wall part (1) having an insertion hole (1A) through which the shield wire (11) is inserted. The shield wire connection structure (10) comprises: the shield wire (11); a plurality of metal connection members (21, 22); a metal cylindrical member (30) that is brought into contact with the plurality of connection members (21, 22) and houses therein the plurality of connection members (21, 22); and a pressing member (40) that retains the plurality of connection members (21, 22) inside the cylindrical member (30). The shield wire (11) has a shield exposure part (16) on which a shield layer (14) is exposed. The plurality of connection members (21,22) are brought into contact with the shield exposure part (16) in a direction orthogonal to the extending direction of the shield exposure part (16), and are disposed around the shield exposure part (16). The cylindrical member (30) is fixed to the hole edge of the insertion hole (1A) in the wall part (1), and is electrically connected to the wall part (1).

Description

Shielded wire connection structure

[0001] The present disclosure relates to a shielded wire connection structure.

[0002] A known structure for introducing and securing a shielded cable into a shielded housing is the shielded cable securing structure described in Japanese Patent Laid-Open Publication No. 8-17485 (Patent Document 1 below). This securing structure includes a flange portion, which is a flange-shaped portion of the shield braid that protrudes, and a shield fixing metal fitting that is fixed to the shielded housing. The flange portion is electrically connected to the shielded housing via the shield fixing metal fitting. The flange portion is formed by peeling back a predetermined length of the insulating outer sheath of the shielded cable to expose the shield braid, and then sliding the insulating outer sheaths on both sides of the exposed shield braid toward each other.

[0003] Japanese Unexamined Patent Publication No. 8-17485

[0004] In the above configuration, the flange must be formed by sliding the insulating outer jacket. Therefore, for example, when connectors or the like are connected to both ends of the shielded cable, forming the flange can be difficult. Furthermore, if the flange is not properly formed, for example, if the shield braid is unevenly distributed in the flange, the shielding performance of the shielded housing can be affected.

[0005] The present disclosure was completed in light of the above circumstances, and has an object to provide a shielded electric wire connection structure that does not require the formation of a flange portion.

[0006] The shielded electric wire connection structure disclosed herein is a shielded electric wire connection structure that connects a shielded electric wire to a metal wall portion having an insertion hole through which the shielded electric wire is inserted, and includes: the shielded electric wire; a plurality of metal connecting members; a metal tubular member that contacts the plurality of connecting members while accommodating the plurality of connecting members; and a pressing member that prevents the plurality of connecting members from coming loose inside the tubular member, wherein the shielded electric wire has a shield exposed portion where the shield layer is exposed, the plurality of connecting members contact the shield exposed portion in a direction perpendicular to the extension direction of the shield exposed portion and are arranged around the shield exposed portion, and the tubular member is fixed to the hole edge portion of the insertion hole in the wall portion and is electrically connected to the wall portion.

[0007] According to the present disclosure, it is possible to provide a shielded electric wire connection structure that does not require the formation of a flange portion.

[0008] Fig. 1 is an exploded perspective view of a shielded electric wire connection structure according to a first embodiment. Fig. 2 is a side view of the shielded electric wire connection structure. Fig. 3 is a rear view of the shielded electric wire connection structure. Fig. 4 is a cross-sectional view taken along line A-A in Fig. 3. Fig. 5 is a cross-sectional view showing the internal structure of a shielded electric wire. Fig. 6 is a perspective view of a plurality of connection members. Fig. 7 is a cross-sectional view of a shielded electric wire connection structure according to a second embodiment, corresponding to Fig. 4.

[0009] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described. [1] A shielded electric wire connection structure of the present disclosure is a shielded electric wire connection structure that connects a shielded electric wire to a metal wall portion having an insertion hole through which the shielded electric wire is inserted, the shielded electric wire connection structure comprising: the shielded electric wire, a plurality of metal connection members, a metal tubular member that contacts the plurality of connection members and accommodates the plurality of connection members, and a pressing member that prevents the plurality of connection members from slipping out from inside the tubular member, the shielded electric wire having a shield exposed portion where a shield layer is exposed, the plurality of connection members contact the shield exposed portion in a direction perpendicular to the extension direction of the shield exposed portion and are arranged around the shield exposed portion, the tubular member is fixed to an edge portion of the insertion hole in the wall portion and is electrically connected to the wall portion.

[0010] With this configuration, a shielded wire connection structure can be easily constructed by forming a shield exposed portion that exposes the shield layer and assembling multiple connection members, a tubular member, and a pressing member to the shield exposed portion, thereby eliminating the need to form a flange by protruding the shield layer in a flange shape.

[0011] [2] In the above [1], it is preferable that the plurality of connecting members have a first inclined surface that is inclined so as to approach the shield exposed portion as it approaches the wall portion in the extension direction of the shield exposed portion, and the tubular member has a second inclined surface that contacts the first inclined surface, and the second inclined surface is inclined so as to approach the shield exposed portion as it approaches the wall portion in the extension direction of the shield exposed portion.

[0012] With this configuration, when the multiple connection members are housed inside the tubular member, the first inclined surface and the second inclined surface slide against each other, causing the multiple connection members to press against the exposed shield portion, thereby improving electrical connection between the multiple connection members and the shield layer.

[0013] [Details of the Embodiments of the Present Disclosure] The following describes embodiments of the present disclosure. The present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims. In the drawings, for the convenience of explanation, some components may be exaggerated or simplified. Furthermore, the dimensional ratios of each part may differ between drawings. In this specification, "orthogonal" does not only refer to a strict orthogonal relationship, but also includes a roughly orthogonal relationship within the scope of the operation and effect of this embodiment.

[0014] First Embodiment A first embodiment of the present disclosure will be described with reference to Figures 1 to 6. In the following description, the direction indicated by arrow Z is the upward direction, the direction indicated by arrow X is the forward direction, and the direction indicated by arrow Y is the leftward direction. In this embodiment, the shield exposed portion 16 of the shielded electric wire 11 will be described as extending in the front-to-rear direction. Note that, for multiple identical components, only some of the components may be designated by reference numerals, and the reference numerals for the other components may be omitted.

[0015] (Shielded electric wire connection structure 10) As shown in Figs. 1 to 4, the shielded electric wire connection structure 10 of this embodiment connects a metal wall 1 and a shielded electric wire 11. The metal wall 1 is, for example, a part of a housing. As shown in Figs. 1 and 4, the shielded electric wire connection structure 10 allows the shielded electric wire 11 to be drawn into the housing through an insertion hole 1A provided in the wall 1, and electrically connects the shielding layer of the shielded electric wire 11 to the housing. The housing houses, for example, a circuit board for high-speed communication. The shielded electric wire connection structure 10 includes the shielded electric wire 11, a plurality of connection members 21, 22, a tubular member 30, and a pressing member 40.

[0016] (Shielded electric wire 11, exposed shield portion 16) As shown in Fig. 5, the shielded electric wire 11 includes a signal wire 12 made of metal, an insulator 13 covering the outer periphery of the signal wire 12, a shield layer 14 covering the outer periphery of the insulator 13, and an outer sheath 15 covering the outer periphery of the shield layer 14. The shield layer 14 is made of metal. The shield layer 14 is, for example, a braided wire formed by weaving thin metal wires. The outer sheath 15 is made of insulating synthetic resin. As shown in Figs. 1 and 4, the shielded electric wire 11 has an exposed shield portion 16 formed by peeling off the outer sheath 15 by a predetermined length in the extension direction of the shielded electric wire 11. The exposed shield portion 16 exposes the shield layer 14 to the outside.

[0017] (Multiple Connection Members 21, 22) The multiple (two in this embodiment) connection members 21, 22 are made of a conductive metal. The metal constituting the multiple connection members 21, 22 is, for example, copper, copper alloy, aluminum, or aluminum alloy. As shown in FIG. 6 , the multiple connection members 21, 22 are combined with each other to form a columnar member 20 having an internal space 20A. The internal space 20A is disposed at a substantially central position when viewed from the extension direction (front-rear direction) of the columnar member 20. The internal space 20A penetrates the columnar member 20. Each connection member 21, 22 has a shape obtained by dividing the columnar member 20 in a direction perpendicular to the front-rear direction. In this embodiment, the columnar member 20 includes a first portion 20B having a substantially cylindrical shape and a second portion 20C having a substantially truncated cone shape. The first portion 20B is disposed behind the second portion 20C. The internal space 20A penetrates the first portion 20B and the second portion 20C. The internal space 20A has a substantially circular shape when viewed from the front-rear direction. Each of the connecting members 21 and 22 has a substantially semicircular shape when viewed from the front-rear direction.

[0018] As shown in FIG. 1 , each connection member 21, 22 has an opposing surface 23 and a recess 24 recessed from the opposing surface 23. The inner surface of the recess 24 is a curved surface that is approximately U-shaped when viewed from the front-rear direction. The recess 24 extends in the front-rear direction. The recess 24 defines an internal space 20A of the columnar member 20 (see FIG. 6 ). The multiple connection members 21, 22 are assembled to the shield exposed portion 16 so as to surround the shield exposed portion 16. For example, one connection member 21 is brought close to the shield exposed portion 16 from below, and the other connection member 22 is brought close to the shield exposed portion 16 from above. The opposing surfaces 23 of the multiple connection members 21, 22 are arranged opposite each other. As shown in FIG. 4 , the recess 24 is arranged around the shield exposed portion 16. The shield exposed portion 16 is arranged in the internal space 20A defined by the recess 24. The inner surface of the recess 24 contacts the shield layer 14 in a direction perpendicular to the extension direction (front-rear direction) of the shield exposed portion 16 .

[0019] The dimension in the front-to-rear direction of the recesses 24 of the connecting members 21, 22 is set to be equal to or slightly smaller than the length of the exposed shield portion 16. This makes it possible to prevent the outer jacket 15 adjacent to the exposed shield portion 16 from being disposed within the recess 24 when the exposed shield portion 16 is surrounded by the multiple connecting members 21, 22. This allows for good contact between the shield layer 14 of the exposed shield portion 16 and the inner surface of the recess 24.

[0020] With the opposing surfaces 23 of the multiple connection members 21, 22 in contact with each other, the dimension of the internal space 20A in a direction perpendicular to the front-to-rear direction is set to be the same as or slightly smaller than the diameter of the shield exposed portion 16. This allows for good contact between the shield layer 14 of the shield exposed portion 16 and the inner surface of the recess 24. Note that in the shielded electric wire connection structure 10, the opposing surfaces 23 of the multiple connection members 21, 22 do not necessarily have to be in contact with each other.

[0021] (First inclined surface 25) As shown in Fig. 4, the connecting members 21, 22 have a first inclined surface 25 that is disposed outside the shield exposed portion 16 and contacts the tubular member 30. The first inclined surface 25 is inclined so as to approach the shield exposed portion 16 as it approaches the wall portion 1 in the extension direction of the shield exposed portion 16. In other words, the first inclined surface 25 is inclined so as to approach the recess 24 in a direction perpendicular to the front-to-rear direction as it extends forward. As shown in Fig. 6, the first inclined surface 25 is a curved surface that corresponds to the outer peripheral surface of the second portion 20C of the columnar member 20.

[0022] (Cylindrical member 30) The cylindrical member 30 is made of a conductive metal. Examples of the metal that makes up the cylindrical member 30 include copper, a copper alloy, aluminum, and an aluminum alloy. As shown in Fig. 4, the cylindrical member 30 has a main body 31 and a housing portion 32 that penetrates the main body 31. The housing portion 32 houses a plurality of connection members 21, 22 that surround the exposed shield portion 16.

[0023] (Second inclined surface 33) The accommodation portion 32 has a first cylindrical portion 32A and a second cylindrical portion 32B connected to the front of the first cylindrical portion 32A. The first cylindrical portion 32A has a substantially cylindrical shape. The second cylindrical portion 32B has a second inclined surface 33 that inclines toward the shield exposed portion 16 in a direction perpendicular to the front-to-rear direction as it extends forward. The second inclined surface 33 is in contact with the first inclined surface 25. The inner circumferential surface of the first cylindrical portion 32A is not in contact with the multiple connecting members 21, 22.

[0024] The housing portion 32 may include a third cylindrical portion 32C that is connected to the front of the second cylindrical portion 32B. A portion of the shielded electric wire 11 that is forward of the exposed shield portion 16 is disposed inside the third cylindrical portion 32C.

[0025] The tubular member 30 includes a flange portion 34 that expands in diameter from the main body portion 31. The flange portion 34 has, for example, a hexagonal shape when viewed from the front-to-rear direction (see FIG. 1 ). The main body portion 31 also includes an insertion portion 35 that is disposed forward of the flange portion 34. The insertion portion 35 is inserted into the insertion hole 1A from the rear of the wall portion 1. A male thread is formed on the outer peripheral surface of the insertion portion 35, and is adapted to threadably engage with a female thread formed on the inner peripheral surface of a nut 50. The nut 50 is threaded onto the insertion portion 35 from the front of the wall portion 1, thereby fixing the tubular member 30 to the wall portion 1.

[0026] (Pressing member 40) The pressing member 40 includes a main cylindrical portion 41, an outer cylindrical portion 42 disposed outside the main cylindrical portion 41, and a connecting portion 43 connecting the main cylindrical portion 41 and the outer cylindrical portion 42. The main cylindrical portion 41 and the outer cylindrical portion 42 are generally cylindrical. The portion of the shielded electric wire 11 rearward of the exposed shield portion 16 is disposed inside the main cylindrical portion 41. The front end surface of the main cylindrical portion 41 contacts the rear end surfaces of the multiple connecting members 21, 22 from behind. The outer cylindrical portion 42 includes a flange portion 42A extending outward from its outer peripheral surface. The flange portion 42A has, for example, a hexagonal shape when viewed from the front-to-rear direction (see FIG. 3). The rear end portion of the tubular member 30 is disposed outside the main cylindrical portion 41 and inside the outer cylindrical portion 42. A female thread is formed on the inner peripheral surface of the outer cylindrical portion 42, and is adapted to threadably engage with a male thread formed on the outer peripheral surface of the rear end portion of the tubular member 30. Therefore, the pressing member 40 is fixed to the cylindrical member 30 while pressing the multiple connecting members 21 and 22 from behind.

[0027] (Assembly of the shielded electric wire connection structure 10) An example of an assembly method of the shielded electric wire connection structure 10 of this embodiment will be described below. First, the nut 50 is placed in front of the wall portion 1, and the tubular member 30, the plurality of connection members 21, 22, and the pressing member 40 are placed behind the wall portion 1. For example, the front of the wall portion 1 is the inside of the housing, and the rear of the wall portion 1 is the outside of the housing.

[0028] 1 , the shielded electric wire 11 is inserted through the tubular main body portion 41 of the pressing member 40, the tubular member 30, the insertion hole 1A of the wall portion 1, and the nut 50. The pressing member 40 is disposed behind the tubular member 30. Connectors or the like may be connected to both ends of the shielded electric wire 11. The inner diameters of the tubular main body portion 41, the tubular member 30, the insertion hole 1A, and the nut 50 may be set so that the connectors or the like can pass through.

[0029] The cylindrical member 30 is fixed to the wall portion 1. More specifically, the insertion portion 35 of the cylindrical member 30 is inserted into the insertion hole 1A, and the nut 50 is screwed onto the insertion portion 35. The edge of the insertion hole 1A in the wall portion 1 is clamped between the flange portion 34 and the nut 50.

[0030] The shield exposed portion 16 is disposed between the pressing member 40 and the cylindrical member 30. A plurality of connecting members 21, 22 are assembled to the shield exposed portion 16, and the shield exposed portion 16 is surrounded by the recess 24. In detail, the opposing surface 23 of one connecting member 21 and the opposing surface 23 of the other connecting member 22 are disposed to face each other, and the shield exposed portion 16 is sandwiched between the plurality of connecting members 21, 22 from above and below.

[0031] The plurality of connecting members 21, 22 surrounding the exposed shield portion 16 are housed in the housing portion 32 of the cylindrical member 30 from the rear.

[0032] With the connecting members 21, 22 housed in the housing 32, the presser member 40 is attached to the tubular member 30 from the rear. Specifically, the male threads at the rear end of the tubular member 30 are threadedly engaged with the female threads of the outer tubular portion 42, thereby securing the pressing member 40 to the tubular member 30. When the pressing member 40 is attached to the tubular member 30, the presser member 40 moves forward relative to the tubular member 30 and presses the connecting members 21, 22 from the rear. Here, the first inclined surfaces 25 of the connecting members 21, 22 slide against the second inclined surfaces 33 of the housing 32, displacing the connecting members 21, 22 toward the shield exposed portion 16 in a direction perpendicular to the front-to-rear direction, and the recesses 24 are pressed against the shield exposed portion 16. This improves the electrical connection between the connecting members 21, 22 and the shield layer 14. This improves the shielding performance of the housing. This completes the assembly of the shielded electric wire connection structure 10.

[0033] As described above, the shielded electric wire connection structure 10 of this embodiment can be easily constructed without the need to form a flange by making the shield layer 14 protrude outward from the outer jacket 15. It is also possible to avoid a situation in which the shielding performance of the housing is affected by the quality of the flange formation. That is, it is easy to stabilize the shielding performance of the housing. Furthermore, since it is not necessary to slide the outer jacket 15 in the extension direction of the shielded electric wire 11 to form the flange, connectors or the like may be connected to both ends of the shielded electric wire 11 at a stage before the shielded electric wire 11 is connected to the wall portion 1.

[0034] (Actions and Effects of First Embodiment) (1) A shielded electric wire connection structure 10 according to the first embodiment is a shielded electric wire connection structure 10 that connects a shielded electric wire 11 to a metal wall portion 1 having an insertion hole 1A through which the shielded electric wire 11 is inserted, and includes: the shielded electric wire 11; a plurality of metal connection members 21, 22; a metal tubular member 30 that is in contact with the plurality of connection members 21, 22 and houses the plurality of connection members 21, 22; and a retaining member 40 that prevents the plurality of connection members 21, 22 from coming off inside the tubular member 30, wherein the shielded electric wire 11 has a shield exposed portion 16 where the shield layer 14 is exposed, and the plurality of connection members 21, 22 are in contact with the shield exposed portion 16 in a direction perpendicular to the extension direction of the shield exposed portion 16 and are arranged around the shield exposed portion 16, and the tubular member 30 is fixed to the hole edge of the insertion hole 1A in the wall portion 1 and is electrically connected to the wall portion 1.

[0035] With this configuration, the shielded electric wire connection structure 10 can be easily configured by forming the shield exposed portion 16 that exposes the shield layer 14, and assembling the multiple connection members 21, 22, the tubular member 30, and the pressing member 40 to the shield exposed portion 16. Therefore, it is not necessary to form a flange by making the shield layer 14 protrude in a flange-like shape.

[0036] (2) In embodiment 1, the multiple connecting members 21, 22 have a first inclined surface 25 that is inclined so that the closer they are to the wall portion 1 in the extension direction of the shield exposed portion 16, the closer they are to the shield exposed portion 16. The tubular member 30 has a second inclined surface 33 that contacts the first inclined surface 25, and the second inclined surface 33 is inclined so that the closer they are to the wall portion 1 in the extension direction of the shield exposed portion 16, the closer they are to the shield exposed portion 16.

[0037] With this configuration, when the plurality of connection members 21, 22 are housed inside the tubular member 30, the first inclined surface 25 and the second inclined surface 33 come into sliding contact with each other, causing the plurality of connection members 21, 22 to press against the exposed shield portion 16. This allows for good electrical connection between the plurality of connection members 21, 22 and the shield layer 14.

[0038] Second Embodiment A second embodiment of the present disclosure will be described with reference to Fig. 7. A shielded electric wire connection structure 110 according to the second embodiment does not have the first inclined surface 25 and the second inclined surface 33 of the first embodiment. Hereinafter, detailed descriptions of the same components and effects as those of the first embodiment may be omitted.

[0039] The shielded electric wire connection structure 110 includes a shielded electric wire 11, a plurality of connection members 121, 122, a tubular member 130, and a pressing member 40. Each of the connection members 121, 122 has a substantially semi-cylindrical shape. Each of the connection members 121, 122 has a first contact surface 126 that is disposed outside the exposed shield portion 16 and contacts the tubular member 130.

[0040] The tubular member 130 includes a main body 131, a housing 132, and a flange 34. The housing 132 includes a third tubular portion 32C and a fourth tubular portion 132D connected to the rear of the third tubular portion 32C. The fourth tubular portion 132D is generally cylindrical. The inner diameter of the fourth tubular portion 132D is larger than the inner diameter of the third tubular portion 32C. Therefore, a step 136 is provided at the rear end of the third tubular portion 32C in the housing 132. A guide portion 137 is provided at the rear end of the inner circumferential surface of the fourth tubular portion 132D. The guide portion 137 is inclined rearward so as to move away from the shielded electric wire 11 in a direction perpendicular to the front-to-rear direction. The guide portion 137 facilitates housing the multiple connection members 21, 22 into the housing 132 from the rear. The inner circumferential surface of the fourth cylindrical portion 132D excluding the guide portion 137 forms a second contact surface 138 that contacts the first contact surface 126. The contact between the first contact surface 126 and the second contact surface 138 electrically connects the multiple connection members 121, 122 and the cylindrical member 130.

[0041] Other Embodiments The above-described first and second embodiments can be modified as follows: The above-described first and second embodiments and the following modifications can be combined and implemented within the scope of technical compatibility.

[0042] The shielded electric wire connecting structure may not include a nut, and the inner circumferential surface of the insertion hole may be formed with a female thread that screws onto the male thread of the insertion portion.

[0043] The shielded wire connection structure may include three or more connection members.

[0044] The shielded wire may include multiple signal wires.

[0045] 1: Wall portion 1A: Insertion hole 10: Shielded electric wire connection structure 11: Shielded electric wire 12: Signal wire 13: Insulator 14: Shield layer 15: Outer sheath 16: Shield exposed portion 20: Pillar-shaped member 20A: Internal space 20B: First portion 20C: Second portion 21, 22: Connection member 23: Opposing surface 24: Recess 25: First inclined surface 30: Cylindrical member 31: Main body portion 32: Storage portion 32A: First cylindrical portion 32B: Second cylindrical portion 32C: Third cylindrical portion 33: Second inclined surface 34: Flange portion 35: Insertion portion 40: Pressing member 41: Main body cylindrical portion 42: Outer cylindrical portion 42A: Flange portion 43: Coupling portion 50: Nut 110: Shielded electric wire connection structure 121, 122: Connection member 126: First contact surface 130: Cylindrical member 131: Main body portion 132: Storage portion 132D: Fourth cylindrical portion 136: Step portion 137: Guide portion 138: Second contact surface

Claims

1. A shielded electric wire connection structure that connects a shielded electric wire to a metal wall portion having an insertion hole through which the shielded electric wire is inserted, comprising: the shielded electric wire; a plurality of metal connection members; a metal tubular member that contacts the plurality of connection members and houses the plurality of connection members; and a retaining member that prevents the plurality of connection members from slipping out from inside the tubular member, wherein the shielded electric wire has a shield exposed portion where the shield layer is exposed, the plurality of connection members contact the shield exposed portion in a direction perpendicular to the extension direction of the shield exposed portion and are arranged around the shield exposed portion, and the tubular member is fixed to the hole edge of the insertion hole in the wall portion and is electrically connected to the wall portion.

2. A shielded electric wire connection structure as described in claim 1, wherein the plurality of connection members have first inclined surfaces that are inclined so as to approach the shield exposed portion as they approach the wall portion in the extension direction of the shield exposed portion, and the tubular member has a second inclined surface that contacts the first inclined surface, and the second inclined surface is inclined so as to approach the shield exposed portion as it approaches the wall portion in the extension direction of the shield exposed portion.

Images