Patent Application
20240047917
This application claims the benefit of Japanese Patent Application No. 2022-124465, filed Aug. 4, 2022, the whole disclosure of which is incorporated herein by reference.
Embodiments of the present disclosure relate to a shield wire assembly including a wire seal or seal member for waterproofing.
According to the prior art, grounding methods for shield wires used in electrical machinery connectors, for example, utilize a shield contact that is pressure bonded with a braided wire. Specifically, according to the prior art, a connector includes a terminal, a contact that comes into contact with a metal shell when pressure bonded and connected with a shield braiding of a shield wire, and a waterproof seal member that is inserted onto an outer periphery of the shield wire.
When this structure is applied to a waterproof connector, a contact (e.g., a ferrule) needs to be disposed in the vicinity of the waterproof seal member (wire seal) for the purpose of reducing size. However, depending on the handling method such as pulling the wire or the like, the ferrule may move and come into contact with the wire seal, thus damaging the wire seal and impairing the waterproof performance. Further, prior art solutions often experience excessive displacement of portions of the ferrule, although the ferrule is grounded with elasticity due to the metal shell and the spring piece, impairing the connection.
Therefore, it is an object of the present disclosure to provide a shield wire assembly capable of preventing damages of the wire seal due to the movement of the ferrule and preventing excessive displacement of the ferrule within the assembly.
According to an embodiment of the present disclosure, a shield wire assembly comprises a shield wire, a conductive ferrule, a wire seal and a stopper. The shield wire includes a central conductor and a braided shielding wire. The ferrule is conductively connected to, and adapted to ground, the braided wire. The stopper is arranged between the ferrule and the wire seal, and includes a first stopper portion suppressing displacement of the ferrule in an inward radial direction and a second stopper portion suppressing displacement of the ferrule in a direction toward the wire seal.
The invention will now be described by way of example with reference to the accompanying Figures, of which:
Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the attached drawings, wherein the like reference numerals refer to the like elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art.
In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.
As illustrated in
Hereinafter, regarding the shield wire assembly 1, its elements will be described in order, and thereafter, the mounting state of the shield wire assembly 1 with respect to a housing 100 of the electrical connector, which is the mounting target, and two functions, the damage preventing function and the excessive displacement preventing function, by the shield wire assembly 1 will be described.
As illustrated in
The core wire 11 may be, for example, a stranded wire formed by twisting a plurality of metal strands, a conductor made of a single body having a solid structure, or the like or that in which such conductors are combined. For the material forming the core wire 11, for example, metal material having excellent electrical conductivity such as copper or copper alloy, aluminum or aluminum alloy, or the like can be used. This is similar for the metal strand of the braided wire 15.
The inner layer covering 13 covers, for example, the outer peripheral surface of the core wire 11 over the entire periphery. The inner layer covering 13 is, for example, formed from an electrical insulating material such as synthetic resin, and specifically, for example, synthetic resin having polyolefin based resin such as crosslinked polyethylene, crosslinked polypropylene or the like as a main component is used. The inner layer covering 13 may be formed from a single type of insulating material, or by appropriately combining a plurality of types of insulating materials in a plurality of layers by way of example.
The braided wire 15 has a tubular form that covers the outer periphery of the inner layer covering 13. For the braided wire 15, a braided wire in which a plurality of metal strands are knitted, or a braided wire in which metal strands and resin strands are knitted in combination can be used. The braided wire 15 has a portion exposed from the outer layer covering 17 folded back toward the rear side (R) at the end on the front side (F). A fold-back portion 15A is sandwiched between the ferrule 40 and a fixed body 30. As a result, the braided wire 15 is electrically connected with the ferrule 40. The outer layer covering 17 covers the entire region in the peripheral direction of the outer peripheral surface of the braided wire 15. The outer layer covering 17 is, for example, formed by an electrical insulating material similar to the inner layer covering 13.
The terminal 19 is connected to the distal end portion of the core wire 11 exposed from the inner layer covering 13. The terminal 19 includes a core wire connecting portion 19A responsible for connection with the core wire 11, and a counter connecting portion 19B integrally formed with the core wire connecting portion 19A and connected with a mating terminal (not illustrated). In the terminal 19, the core wire connecting portion 19A and the counter connecting portion 19B are integrally formed by, for example, stamping a plate material made of metal material excelling in electrical conductivity, and performing machine processing such as forming.
The core wire connecting portion 19A is, for example, also connected mechanically, in addition to being electrically connected with the core wire 11 through means such as pressure bonding and welding. The counter connecting portion 19B is formed with a fastening hole 19C penetrating in a plate thickness direction thereof for connection by fastening with the mating terminal. For example, electrical and mechanical connection with the mating terminal (not illustrated) are realized with a bolt (not illustrated) inserted into the fastening hole 19C.
As shown in
The fixed body 30 is mated with a pressure bonding portion 41 of the ferrule 40 from the outer side, and applies a load toward the inner side in the radial direction at an appropriate position in the peripheral direction, so that the pressure bonding portion 41 is caulked or sealed and mechanically restrained in a state of sandwiching the braided wire 15 in between. According to such a caulking, a stable electrical connection between the braided wire 15 and the ferrule 40 is ensured. In addition, the pressure bonding portion 41 is pressure bonded to the outer layer covering 17 of the shield wire 10, and the ferrule 40 is fixed at a predetermined position of the shield wire.
The material forming the fixed body 30 is not limited, and may be selected from an iron based, aluminum based, copper based metal material or the like. The fixed body 30 is typically formed as a cylindrical member, and includes a mating hole 31 where the pressure bonding portion 41 is interiorly located and a caulking or sealing ring 33 that surrounds the mating hole. The caulking ring 33 is embodied as the fixed body 30, but the form of the fixed body may be arbitrary as long as electrical connection with the braided wire 15 can be made in addition to fixing the pressure bonding portion 41 to the shield wire 10.
The ferrule 40 includes the pressure bonding portion 41 pressure bonded to the shield wire 10 at a predetermined position of the shield wire by being caulked by the fixed body 30, and a connecting portion 43 electrically connected to the housing 100. The pressure bonding portion 41 and the connecting portion 43 are respectively formed as an annular shape. However, the diameter of the pressure bonding portion 41 is relatively small. The pressure bonding portion 41 and the connecting portion 43 are integrally formed from a metal material having electrical conductivity similar to the fixed body 30. The ferrule 40 can be produced, for example, by bending a flat plate material to a circular ring shape. Furthermore, the ferrule 40 can be produced by preparing a circular tube of the same shape as the pressure bonding portion 41, and enlarging the diameter and shaping the portion corresponding to the connecting portion 43. The pressure bonding portion 41 has a simple circular tube shape by way of example.
The connecting portion 43 includes a front side supporting end 43A, a rear side supporting end 43B provided with a space in a direction of an axis line (C), and a plurality of elastic pieces 44 and a plurality of stationary pieces 45 provided between the front side supporting end and the rear side supporting end. When the ferrule 40 is mounted to the shield wire 10, the elastic piece 44 is positioned on the front side (F), and the rear side supporting end 43B is positioned on the rear side (R). The front side supporting end 43A and the rear side supporting end 43B are both formed in continuation in the peripheral direction.
Each of the elastic pieces 44 has a cantilever beam form in which the front side supporting end 43A side serves as a free end 44A, and the rear side supporting end 43B side serves as a fixed end 44B continuing to the rear side supporting end 43B. Each of the elastic pieces 44 is formed with a contact 44C responsible for direct connection with the housing 100. The contact 44C is formed to rise toward the outer side in the radial direction of the elastic piece 44. In the elastic piece 44, the lateral cross sectional view excluding the contact 44C, that is, the surface orthogonal to the axis line (C) has an arcuate form. This is the same for the stationary piece 45.
Each of the stationary pieces 45 has a double supported beam form in which the front side supporting end 43A side serves as a fixed end 45A continuing to the front side supporting end 43A, and the rear side supporting end 43B side serves as a fixed end 45B continuing to the rear side supporting end 43B. The stationary piece 45 may deform as it is a plate-like member made of metal material, or an elastic body, but is referred to as the stationary piece 45 as it is stationary in comparison with the elastic piece 44.
The plurality of elastic pieces 44 and the plurality of stationary pieces 45 are alternately provided in the peripheral direction between the front side supporting end 43A and the rear side supporting end 43B. Furthermore, the elastic piece 44 and the stationary piece 45 have an equal radial dimension from the axis line (C). The plurality of elastic pieces 44 and the plurality of stationary pieces 45 are alternately positioned on or in the arc.
A stopper 50 capable of being positioned between the fixed body 30 and the wire seal 60 and providing a damage preventing effect and an excessive displacement preventing effect will be described with reference to
The first stopper 51 is provided to prevent the elastic piece 44 of the ferrule 40 from being excessively displaced toward the inner side in the radial direction (D) by being positioned between the outer layer covering 17 of the shield wire 10 and the ferrule 40. The first stopper 51 includes an inner peripheral surface 51A and an outer peripheral surface 51B. The first stopper 51 includes a displacement permitting portion 52 positioned on the front side (F) and a displacement regulating portion 53 positioned on the rear side (R) of the displacement permitting portion. The elastic piece 44 of the ferrule 40 is positioned in the displacement permitting portion 52 with a gap on the outer side in the radial direction (D). In the displacement regulating portion 53 is positioned, with a gap, the rear side supporting end 43B of the ferrule 40 on the outer side in the radial direction (D).
The outer diameter D52 of the displacement permitting portion 52 is formed smaller than the outer diameter D53 of the displacement regulating portion 53 (see
A plurality of projections 54 extending in the direction of the axis line (C) are positioned at equal interval in the peripheral direction in the inner peripheral surface 51A of the first stopper 51. The distal end toward the inner side in the radial direction (D) of the projection 54 is pointed. When the shield wire 10 is mated to the inner side of the stopper 50, the projection 54 bites into the outer layer covering 17 of the shield wire, so that the relative position shift in the peripheral direction of the shield wire and the stopper can be prevented.
The second stopper 55 blocks the ferrule 40 from moving toward the wire seal 60 and exhibits the damage or scar preventing function of preventing the wire seal 60 from being damaged when the connecting portion 43 of the ferrule 40 is brought into contact by being positioned between the end on the rear side (R) of the connecting portion of the ferrule and the wire seal. To this end, the second stopper 55 is formed to satisfy D55≥D43, where D55 is the dimension in the radial direction (D) of the second stopper 55 (flange 55A) and D43 is the dimension in the radial direction of the connecting portion 43 (see
The second stopper 55 includes the flange 55A projecting out from the end on the rear side (R) of the first stopper 51 toward the outer side in the radial direction (D), and a ring-shaped rib 55B extending from the end (distal end) in the radial direction (D) of the flange toward the front side (F) so as to be parallel to the first stopper. The flange 55A protects the wire seal 60 by having the ferrule 40 attempting to move toward the wire seal 60 collide thereto. The rib 55B restrains the displacement in the radial direction (D) of the connecting portion 43 and positions the connecting portion 43 by sandwiching the connecting portion of the ferrule 40 with the displacement regulating portion 53.
The wire seal 60 is provided between the housing 100 and the outer layer covering 17 of the shield wire 10, and is closely attached to both the housing and the outer layer covering, thus preventing moisture from entering inside the housing through the outer layer covering. The wire seal 60 includes a wire seal portion 61 closely attached to the outer peripheral surface of the outer layer covering 17 of the shield wire 10, and a housing seal portion 63 closely attached to the inner peripheral surface of the housing 100. The wire seal 60 is, for example, made from rubber material such as silicon rubber, nitrile rubber, and fluorine rubber.
As shown in
The wire accommodating space 101 includes, by way of example, a smaller space 101A positioned on the front side (F) and a larger space 101B positioned on the rear side (R) of the smaller space. The smaller space 101A and the larger space 101B are both made of circular column shaped cavity, but the larger space has a larger diameter than the smaller space. A step difference 101C is formed at the boundary of the smaller space 101A and the larger space 101B. An inner peripheral surface of the housing 100 facing the smaller space 101A configure an electric contact surface 101D to which the contact 44C of the elastic piece 44 of the ferrule 40 is electrically connected. The inner peripheral surface of the housing 100 facing the larger space 101B configure a seal surface 101E to which a housing seal portion 63 of the wire seal 60 is closely attached. The end on the rear side (R) of the larger space 101B is an opening 101F communicating to the outside, and the opening is closed by a fastener 103.
As shown in
In the smaller space 101A, the braided wire 15 and the ferrule 40 are electrically connected by sandwiching the fold-back portion 15A between the pressure bonding portion 41 of the ferrule 40 and the caulking ring 31 of the fixed body 30 between the braided wire 15. Furthermore, in the smaller space 101A, the necessary and sufficient displacement toward the inner side in the radial direction (D) of the elastic piece 44 at the periphery of the displacement permitting portion 52 is permitted.
In the larger space 101B, the displacement toward the inner side in the radial direction (D) is restrained by the displacement regulating portion 53 in which the rear side supporting end 43B is provided on the inner side thereof. In addition, the rear side supporting end 43B has the displacement on the outer side in the radial direction (D) restricted by the rib 55B. The contact 44C of the elastic piece 44 comes into contact with the electric contact surface 101D. Furthermore, the flange 55A is positioned on the rear side (R) of the rear side supporting end 43B. The rib 55B continuing to the distal end in the radial direction (D) of the flange 55A has the end on the front side (F) butting against the step difference 101C, so that the displacement toward the front side of the stopper 50 is restricted. The displacement toward the rear side (R) of the stopper 50 is restricted by the fastener 103 by way of the wire seal 60.
The shield wire assembly 1 has the following effects by including the stopper 50. The stopper 50 includes the first stopper 51 provided on the inner side of the ferrule 40. Therefore, according to the shield wire assembly 1, the excessive displacement preventing effect of preventing the ferrule 40 from making an excessive displacement toward the inner side in the radial direction (D) can be obtained. Furthermore, the stopper 50 includes the second stopper 55 on the rear side (R) of the rear side supporting end 43B of the ferrule 40. Therefore, according to the shield wire assembly 1, the ferrule 40 is displaced toward the rear side (R) and butts against the wire seal 60, and the damage or scar preventing effect of preventing scrapes from forming in the wire seal 60 can be obtained. In addition, the shield wire assembly 1 has two effects, the excessive displacement preventing effect and the scar preventing effect, by providing the stopper 50, which is a single member formed as one piece, and thus also has superiority in terms of cost.
As described above, preferred embodiments of the present invention have been described, but other than the embodiments described above, configurations described in the above embodiments can be selected or appropriately changed to other configurations as long as they are not deviated from the general concepts of the present invention. For example, in a preferred form, the stopper 50 has the first stopper 51 having the excessive displacement preventing function and the second stopper 55 exhibiting the scar preventing function integrally formed, but the present invention is not limited thereto. A member corresponding to the first stopper 51 and a member corresponding to the second stopper 55, which are individually produced, may be positioned at positions in the shield wire assembly 1 corresponding to the first stopper and the second stopper, respectively. Further, while the connecting portion 43 of the ferrule 40 includes the elastic piece 44 of cantilever beam form, but may also be a simple cylindrical form. In this form as well, the contact 44C or a site corresponding to the contact 44C is preferably provided to reliably obtain the electrical connection with the electric contact surface 101D of the housing 100.
In addition, those areas in which it is believed that those of ordinary skill in the art are familiar, have not been described herein in order not to unnecessarily obscure the invention described. Accordingly, it has to be understood that the invention is not to be limited by the specific illustrative embodiments, but only by the scope of the appended claims.
It should be appreciated for those skilled in this art that the above embodiments are intended to be illustrated, and not restrictive. For example, many modifications may be made to the above embodiments by those skilled in this art, and various features described in different embodiments may be freely combined with each other without conflicting in configuration or principle.
Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.
As used herein, an element recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of the elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2022-124465 | Aug 2022 | JP | national |
