Patent Publication Number: US-11043769-B2

Title: Combined inner housing connector for vehicle

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates to a connector for high-speed transmission for a vehicle. 
     Related Art 
     Communications between on-board devices of a motor vehicle or communications between an on-board device and an external device, have been progressively enhanced in speed. A connector has been proposed for a wire harness adaptable to the high-speed communication (Japanese Patent Application Laid-open No. 2018-152215). 
     The connector includes a terminal unit and a housing for housing the terminal unit. The terminal unit has a first component and a second component. The first component and the second component each are formed of a dielectric. The first component and the second component are mutually combinable. The first component is provided with two terminal-housing chambers comparted by a partition wall and one cable-housing chamber in communication with the two terminal-housing chambers. The two terminal-housing chambers and the one cable-housing chamber are entirely open on the upper side. The first component is combined with the second component, resulting in occlusion of the opening on the upper side of the first component. 
     Terminals connected with two sheathed cables of a twisted cable are housed one-to-one in the two terminal-housing chambers. The sections in which the twists of the two sheathed cables are released, are housed in the cable-housing chamber. 
     For the assembly of the terminal unit, the two terminals are inserted through the openings on the upper side of the two terminal-housing chambers of the first component, and the two sheathed cables having the twist released are inserted through the opening on the upper side of the cable-housing chamber. Next, the first component and the second component are assembled into a combination. 
     SUMMARY 
     However, according to the previous example, for the assembly of the first component and the second component, because the terminal-housing chambers and the cable-housing chamber of the first component are open on the upper side, the second component is assembled so as to occlude the openings on the upper side. 
     In this case, because the two sheathed cables having the twist released, have a tendency to twist, the sheathed cables are likely to be pinched (caught) between the contact faces of the first component and the second component. When the first component and the second component are assembled forcibly with the sheathed cables pinched (caught) between the contact faces of the first component and the second component, the core (strand) of each sheathed cable is likely to break. 
     Thus, the present disclosure has been made in order to solve the issue, and an object of the present disclosure is to provide a connector enabling a sheathed cable to be prevented from being pinched (caught) in cable-housing work. 
     According to an embodiment of the present disclosure, provided is a connector including: 
     a combined inner housing formed of a first inner housing and a second inner housing in combination, the first inner housing having a plurality of insertion holes mutually independent, the first inner housing being formed of a first dielectric or an electric conductor, the second inner housing having a plurality of terminal-housing chambers mutually independent, the second inner housing being formed of a second dielectric, the plurality of insertion holes being in one-to-one communication with the plurality of terminal-housing chambers; 
     a twisted-pair cable having a plurality of sheathed cables, each sheathed cable having a twist released, having an end connected with a terminal, the plurality of terminals being housed one-to-one in the terminal-housing chambers by one-to-one insertion of the terminals in the terminal-housing chambers of the combined inner housing, twist-released sections in which the twists of the sheathed cables are released, being housed one-to-one in the insertion holes by one-to-one insertion of the twist-released sections of the sheathed cables in the insertion holes of the combined inner housing; 
     a shield member that covers the combined inner housing; and 
     an outer housing that houses the combined inner housing and the shield member. 
     According to the embodiment of the present disclosure, for cable-housing work, the sheathed cables each connected with the terminal require at least inserting in the mutually independent insertion holes of the combined inner housing. Thus, no pinching (catching) of the sheathed cables occurs in the cable-housing work. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a side view of a connector according to an embodiment of the present disclosure; 
         FIG. 2  is a sectional view of the connector according to the embodiment of the present disclosure; 
         FIG. 3  is a perspective view of a shield member, a first inner housing, a second inner housing, and a twisted cable, according to the embodiment of the present disclosure; 
         FIG. 4  is a perspective view of a process of insertion of the end portions of twisted-pair cables of the twisted cable into a combined inner housing, according to the embodiment of the present disclosure; and 
         FIG. 5A  is a sectional view of terminals having been housed, and  FIG. 5B  is a sectional view of sheathed cables having been housed, according to the embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     An embodiment of the present disclosure will be described below with reference to the accompanying drawings. 
       FIGS. 1 to 5  illustrate the embodiment of the present disclosure. A wire harness is a constituent for a high-speed transmission circuit of a motor vehicle. For example, the transmission frequency band thereof is 5 GHz (10 Gbps). The wire harness has a twisted cable  1  and a connector  10  connected with the twisted cable  1 . 
     The twisted cable  1  has a tubular insulating outer sheath  2 , a tubular shield braided wire  3  and metallic foil (not illustrated) arranged inside the insulating outer sheath  2 , and two twisted-pair cables  5  arranged inside the shield braided wire  3  and the metallic foil (not illustrated). The metallic foil (not illustrated) has an end part cut. The shield braided wire  3  has an end part not cut but folded over a ring  8  arranged on the outer circumferential face of the insulating outer sheath  2 . 
     The two twisted-pair cables  5  each have an end portion exposed outside. Each twisted-pair cable  5  has two sheathed cables  6 . Each sheathed cable  6  has a core  6   a  and an insulating outer sheath  6   b  sheathing the outer circumferential side of the core  6   a.    
     The two sheathed cables  6  of each twisted-pair cable  5  are twisted together in the section in which the two twisted-pair cables  5  are arranged inside the shield braided wire  3 . However, the two sheathed cables  6  of each twisted-pair cable  5  have the twist released in the section in which the two twisted-pair cables  5  are exposed outside. At the end of each of the four sheathed cables  6  having the twist released, the core  6   a  is exposed with the insulating outer sheath  6   b  peeled. Each exposed core  6   a  is connected with a terminal  7  (refer to  FIG. 3 ). At least the four terminals  7  and the twist-released sections in which the twists of the four sheathed cables  6  are released, are housed in the connector  10 . 
     The connector  10  includes a first inner housing  11 , a second inner housing  20 , a shield member  30 , and an outer housing  40 . 
     The first inner housing  11  is formed of a first dielectric (e.g., glass-fiber-containing polybutylene terephthalate) or an electric conductor (e.g., electrically conductive resin (e.g., carbon-containing polybutylene terephthalate)). 
     The first inner housing  11  has four insertion holes  13  independent in non-communication with each other. The four insertion holes  13  are arranged in two rows vertically and crosswise. Partition walls  14   a  and  14   b  formed of the first dielectric are interposed between each insertion hole  13 . The partition wall  14   a  comparts the insertion holes  13  in the crosswise direction, and the partition wall  14   b  comparts the insertion holes  13  in the vertical direction (refer to  FIG. 5B ). 
     The first inner housing  11  has a substantially quadrangular block shape. The first inner housing  11  has outer faces in the crosswise direction, provided with a pair of locking protrusions  15 . 
     The second inner housing  20  is formed of a second dielectric (e.g., polybutylene terephthalate). 
     The second inner housing  20  has four terminal-housing chambers  21  independent in non-communication with each other. The four terminal-housing chambers  21  are arranged in two rows vertically and crosswise, similarly to the insertion holes  13 . Partition walls  24   a  and  24   b  formed of the second dielectric are interposed between each adjacent terminal-housing chamber  21 . The partition wall  24   a  comparts the terminal-housing chambers  21  in the crosswise direction, and the partition wall  24   b  comparts the terminal-housing chambers  21  in the vertical direction (refer to  FIG. 5A ). The second inner housing  20  is provided with lances  23  protruding one-to-one to the terminal-housing chambers  21  (refer to  FIG. 2 ). 
     The second inner housing  20  has a substantially quadrangular block shape identical in size to that of the first inner housing  11 , on the rear side thereof and has a cylindrical block shape on the front side thereof. The second inner housing  20  has outer faces in the crosswise direction on the rear side thereof, provided with a pair of lock arms  22 . The pair of lock arms  22  protrudes backward. 
     The front face of the first inner housing  11  comes close so as to abut on the rear face of the second inner housing  20 . Then, the pair of lock arms  22  locks together with the pair of locking protrusions  15 , so that the first inner housing  11  and the second inner housing  20  are combined. The combination results in a combined inner housing  25  (refer to  FIG. 4 ). The first inner housing  11  and the second inner housing  20  are combined in the longitudinal direction of the twisted cable  1 . 
     When the combined inner housing  25  is viewed from the front side thereof or from the rear side thereof, the four insertion holes  13  are in one-to-one communication with the four terminal-housing chambers  21 . 
     The terminals  7  are inserted one-to-one in the terminal-housing chambers  21  of the combined inner housing  25  through the rear openings. The twist-released sections of the sheathed cables  6  are inserted one-to-one in the insertion holes  13  of the combined inner housing  25  through the rear openings. Each terminal  7  is retained and housed with a locking protrusion  9  thereof locking together with the lance  23  of the terminal-housing chamber  21 . In addition, the twist-released section of each sheathed cable  6  is housed in the insertion hole  13 . 
     The sheathed cables  6  of each twisted-pair cable  5  are housed in the crosswise adjacent insertion holes  13 , and the terminals  7  are housed in the crosswise adjacent terminal-housing chambers  21 . 
     The shield member  30  has a frame shape similar to the outer shape of the combined inner housing  25 . A cylindrical-hollow swage portion  30   a  protruding is provided on the rear end side of the shield member  30 . The shield member  30  houses the combined inner housing  25  and the folded portion of the shield braided wire  3 . The swage portion  30   a  of the shield member  30  is swaged with the shield braided wire  3  by swaging. The shield braided wire  3  and the shield member  30  are constituents for an electromagnetic shield circuit. Each sheathed cable  6  inside is electromagnetically shielded by the electromagnetic shield circuit from the outside of the twisted cable  1 . 
     The outer housing  40  has a component-housing chamber  41 . The shield member  30  in which the combined inner housing  25  is embedded, is housed in the component-housing chamber  41 . The outer housing  40  has a rear end portion provided with a rubber-stopper-housing groove  42  opening at the inner circumferential face of the component-housing chamber  41 . A ring-shaped rubber stopper  47  is housed in the rubber-stopper-housing groove  42 . The rubber stopper  47  compressed and deformed, adheres closely to the entire of the outer circumference of the twisted cable  1 . Thus, the rubber stopper  47  prevents, for example, water flowing along the twisted cable  1 , from infiltrating into the outer housing  40 . The rubber stopper  47  is retained in position by a cover  48  attached to the rear end portion of the outer housing  40 . 
     A mating-connector fitting portion  43  is provided on the front end side of the outer housing  40 . A ring-shaped hood portion  45  is provided apart through a connector fitting space  44  from the outer circumference of the mating-connector fitting portion  43 . The outer circumferential face of the mating-connector fitting portion  43  is provided with a gasket  46 . With a mating connector  49  fit in the outer housing  40  (illustrated with an imaginary outline in  FIG. 2 ), the gasket  46  prevents, for example, water from infiltrating into the combined inner housing  25 . 
     Next, the impedance between the two terminals  7  connected with each twisted-pair cable  5  and the impedance between the two sheathed cables  6  each in the twist-released section in a case where the first inner housing  11  is formed of the first dielectric, will be described. The impedance ZO between conductors between which a dielectric is interposed, can be calculated with the following expression:
 
 ZO =(276/√ε)·{ln(2 P/d )}
 
     where d represents the width of each conductor, P represents the pitch between the adjacent conductors, and s represents the permittivity of the dielectric. 
     According to the present embodiment, as illustrated in  FIGS. 5A and 5B , the width d 1  of each terminal  7  is larger in size than the width d 2  of the core  6   a  of each sheathed cable  6  (d 1 &gt;d 2 ). The pitch P 1  between adjacent terminals  7  is identical in size to the pitch P 2  between the cores  6   a  of the adjacent sheathed cables  6  (P 1 =P 2 ). On the basis of the above expression, the second inner housing  20  and the first inner housing  11  are formed of respective dielectrics different in permittivity such that the impedance between the two terminals  7  is substantially identical in value to the impedance between the two sheathed cables  6  each in the twist-released section. Specifically, the first dielectric of the first inner housing  11  is formed of a material large in permittivity, and the second dielectric of the second inner housing  20  is formed of a material smaller in permittivity than the material of the first dielectric. 
     That is the pitch P 1  between the adjacent terminals  7  is matched in impedance by the second inner housing  20  formed of the second dielectric, and the pitch P 2  between the adjacent sheathed cables  6  is matched in impedance by the first inner housing  11  formed of the first dielectric. 
     As described above, the connector  10  includes the combined inner housing  25  resulting from the first inner housing  11  and the second inner housing  20  in combination. The first inner housing  11  having the plurality of mutually independent insertion holes  13 , is formed of the first dielectric or the electric conductor. The second inner housing  20  having the plurality of mutually independent terminal-housing chambers  21 , is formed of the second dielectric. The combined inner housing  25  has the plurality of insertion holes  13  in one-to-one communication with the plurality of terminal-housing chambers  21 . Each of the ends of the plurality of sheathed cables  6  having the twist released in each twisted-pair cable  5 , is connected with the terminal  7 . The terminals  7  are inserted one-to-one in the terminal-housing chambers  21  of the combined inner housing  25 , and the twist-released sections in which the twists of the sheathed cables  6  are released, are inserted one-to-one in the insertion holes  13  of the combined inner housing  25 . Thus, each terminal  7  is housed in the terminal-housing chamber  21 , and the twist-released section of each sheathed cable  6  is housed in the insertion hole  13 . The combined inner housing  25  is covered with the shield member  30 . The combined inner housing  25  and the shield member  30  are housed in the outer housing  40 . 
     Therefore, for cable-housing work, the sheathed cables each connected with the terminal  7  require at least inserting in the mutually independent insertion holes  13  of the combined inner housing  25 . Thus, no pinching (catching) of the sheathed cables  6  occurs in the cable-housing work. 
     In a case where the first inner housing  11  is formed of the first dielectric, the impedance between adjacent terminals  7  and the impedance between the adjacent sheathed cables  6  are matched, respectively, by the second inner housing  20  and the first inner housing  11  varied in permittivity. Therefore, a signal waveform can be transmitted with higher fidelity in a transmission channel, with reduction of waveform distortion resulting from reflected waves. 
     Note that, according to the embodiment, the twisted cable  1  has the two twisted-pair cables  5 . However, the present disclosure can be applied to even a twisted cable having one twisted-pair cable or a twisted cable having three twisted-pair cables or more.