Patent Publication Number: US-8992242-B2

Title: Electrical connector assembly

Description:
FIELD OF THE INVENTION 
     The invention relates to connector assemblies, for instance power connector assemblies for electricity-fuel hybrid vehicles or fully electrically vehicles. 
     BACKGROUND OF THE INVENTION 
     Recent trends in the automotive industry concern these electricity-fuel hybrid vehicles or fully electrical vehicles which are powered by batteries through cables with high current and/or voltage. 
     Electrical connector assemblies are used to electrically connect the battery to electrical engines or other electrical devices. For instance the connector assembly comprises a pair of connectors adapted to be coupled one to another; a first connector is connected to the battery side, and a second complementary connector is connected to an electrical device or engine. 
     Electrical connectors usually comprise an insulating casing and electrical terminals. The electrical terminals of both connectors are to be put in electrical contact with each other, while the casings are mechanically connected to each other. For automotive applications a stringent requirement has to be met in terms of watertightness performance. Indeed, the connector assemblies are usually installed in the engine compartment and are therefore exposed to harsh environment in particular to water, dust, etc. Leakage within the connector assembly has to be avoided to prevent short-circuit and corrosion of the metallic terminals. To this end it is known in the prior art to implement water sealing means in the connector assembly that acts as barrier against water. In conventional connector assembly, the sealing means comprises an interfacial sealing joint and/or, in the case of a cable connector, cable seals placed around the electrical wire in order to seal the opening of each chamber to prevent entry of water, moisture or dust from the cable entry side. 
     Furthermore connector assemblies are used to transmit power. Due to the high current and voltage (e.g. 250 A, 600V), it is necessary to provide means to prevent any possible physical contact of the user with the power terminal. At this end, it is known to design the connector housing with touchproof means, such as walls to hinder access to the terminals. 
     It is an object of the present invention to answer the demand for more reliable and safer connector assemblies, i.e. an improved waterproof connector assembly where the terminal are protected by a touchproof means. 
     SUMMARY OF THE INVENTION 
     To this aim, it is provided an electrical connector assembly comprising a first connector having a first casing and a first power contact, and a second connector having a second casing and a first power contact. Of course, the electrical connector assembly of the invention may comprise first and second connectors provided with more than one power contact. The first and second connectors selectively mate and unmate along a mating axis to electrically connect the first power contacts together. The first connector comprises a cylindrical socket surrounding the first power contact of the first connector and the second connector comprises a cylindrical sleeve surrounding the first power contact of the second connector. The cylindrical socket is adapted to surround the cylindrical sleeve when the first and second connectors mate. 
     A sealing system is provided on the second casing and comprises a frontward portion and a rearward portion. The frontward portion surrounds the cylindrical sleeve to seal between the cylindrical socket and the cylindrical sleeve when the first and second connectors mate. The rearward portion surrounds the rear housing of the second casing to seal between the housing of the first casing and the rear housing of the second casing when the first and second connectors mate. 
     With these features, the electrical connector assemblies of the present invention are watertight. A first sealing barrier is provided between the socket(s) and the casing and a second sealing barrier is provided between the socket(s) and the sleeve(s); the purpose of the second sealing is to provide an additional sealing in case the first sealing fails. Further the sealing system of the present invention is suitable for connectors having sleeve members whose function is to protect the terminal from being touched by the user. 
     In various embodiments of the invention, one and/or the other of the features defined in the claims may be incorporated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other characteristics and advantages of the invention will readily appear from the following description of some of its embodiments, provided as non-limitative examples, and of the accompanying drawings. 
       On the drawings: 
         FIG. 1  is a perspective view of a first connector of a connector assembly according to an embodiment, 
         FIG. 2  is a perspective view of a second connector provided with a sealing system and intended to mate with the first connector of  FIG. 1 , 
         FIG. 3A  is schematic section of a sealing system according to an embodiment and provided on a connector assembly, 
         FIG. 3B  is schematic view of a sealing system according to another embodiment and provided on a connector assembly, 
         FIG. 4  is a perspective view of a first connector of a connector assembly according to another embodiment, 
         FIG. 5A  is a perspective view of a second connector intended to mate with the first connector of  FIG. 4 , 
         FIG. 5B  is a perspective view of the second connector of  FIG. 5A  provided with a sealing system, 
         FIG. 6A  is a perspective view of the sealing system provided on the second connector of  FIG. 5B , 
         FIG. 6B  is an upper view of the sealing system of  FIG. 6A , 
         FIG. 6C  is a lateral view of the sealing system of  FIG. 6A , 
         FIG. 7  is a cross-sectional view of the connector assembly obtained after mating the first connector of  FIG. 4  with the second connector of  FIG. 5B , 
         FIG. 8  is a perspective view of a first connector of a connector assembly according to another embodiment, 
         FIG. 9A  is a perspective view of a second connector intended to mate with the first connector of  FIG. 1 , 
         FIG. 9B  is a perspective view of the second connector of  FIG. 9A  provided with a sealing system, 
         FIG. 10A  is a perspective view of the sealing system provided on the second connector of  FIG. 9B , 
         FIG. 10B  is an upper view of the sealing system of  FIG. 10A , 
         FIG. 10C  is a lateral view of the sealing system of  FIG. 10A , 
         FIG. 11  is a perspective view of a first connector of a connector assembly according to another embodiment, 
         FIG. 12A  is a perspective view of a second connector intended to mate with the first connector of  FIG. 11 , 
         FIG. 12B  is a perspective view of the second connector of  FIG. 12A  provided with a sealing system, 
         FIG. 13A  is a perspective view of the sealing system provided on the second connector of  FIG. 12B , 
         FIG. 13B  is an upper view of the sealing system of  FIG. 13A , 
         FIG. 13C  is a lateral view of the sealing system of  FIG. 13A , and 
         FIG. 14  is a schematic view of a system before mating. 
     
    
    
     On the different Figures, the same reference signs designate like or similar elements. 
     DETAILED DESCRIPTION 
       FIG. 1  shows in details a first connector  10  to mate along a longitudinal mating axis X-X with a second connector  12  illustrated on  FIG. 2 . 
     The first connector  10  comprises a cylindrical socket  14  surrounding a first terminal, e.g. a power terminal (not visible on the figures), and extending along the mating axis X-X from a base casing  16 . The socket  14  is delimited by a first housing  18  which surrounds the cylindrical socket  14 . An outer housing  20  is further provided, surrounding the first housing  18 . The inner and outer housings  18  and  20  define an annular space  22 . 
     The second connector of  FIG. 2  comprises a cylindrical sleeve  24 , surrounding a second terminal (not visible on the figures), and extending along the mating axis X-X from a rear housing  25  provided on a second casing  26 . The cylindrical socket  14  is designed to receive this cylindrical sleeve  24  when the first and second connectors mate together along the mating axis X-X. 
     In order to ensure a sealing between the two connectors  10  and  12 , the second casing  26  is provided with a sealing system  28 . The sealing system  28  comprises a frontward portion  30  surrounding the cylindrical sleeve  24  to ensure a sealing between the cylindrical socket  14  and the cylindrical sleeve  24  and a rearward portion  32  surrounding the rear housing  25  of the second casing  26  to ensure a sealing between the inner housing  18  of the first casing  16  and the rear housing  25  of the second casing  26  when the first and second connectors  10  and  12  mate. 
     These frontward  30  and rearward  32  portions can be separate pieces as depicted on  FIG. 2  or the sealing system  28  can be of one piece as depicted on  FIGS. 6A-C ,  10 A-C and  14 A-C for other embodiments, the frontward portion being integral with the rearward portion. 
     Each one of the frontward portion and rearward portion of the sealing system  28  achieve either an axial compression sealing with regard to the mating axis X-X (as schematically illustrated on  FIG. 3A ) or a radial compression sealing with regard to the mating axis X-X as schematically illustrated on  FIG. 3B . 
     In the embodiment illustrated on  FIGS. 4 ,  5 A-B,  6 A-C,  7  and  8 , the connector assembly comprises two pairs of power terminals, one pair on each connector. 
     With reference to  FIG. 4 , the first connector  10  comprises a first cylindrical socket  14 A surrounding a first power terminal and respectively a second cylindrical socket  14 B surrounding a second power terminal. Both first  14 A and second  14 B cylindrical sockets extend along the mating axis X-X from a base casing  16 . The base casing  16  is provided with an inner housing  18  surrounding jointly the first  14 A and second  14 B cylindrical sockets and an outer housing  20  surrounding the inner housing  18 . Since the two sockets are provided side by side, the outer contour of the inner housing  18  and of the outer housing  20  may therefore have an oval shape. The inner and outer housings  18  and  20  define an annular space  22 . 
     The second connector  12  intended to mate with this first connector  10  of  FIG. 4  is illustrated on  FIGS. 5A and 5B . 
     The second connector  12  comprises a two cylindrical sleeve  24 A, 24 B, each of which receiving a complementary power terminal. Both first  24 A and second  24 B cylindrical sleeves extend along the mating axis X-X from a second casing  26 . Each cylindrical socket of the first connector is adapted to receive internally the corresponding cylindrical sleeve of the second connector when the first and second connectors mate together along the mating axis X-X. In order to provide a sealing between the two connectors  10  and  12 , the second (plug) connector  12  is provided with a sealing system  28  as illustrated on  FIG. 5B . 
     The sealing system  28  comprises a first frontward portion  30 A surrounding the first cylindrical sleeve  24 A to ensure a sealing between the first cylindrical socket  14 A and the first cylindrical sleeve  24 A and a second frontward portion  30 B surrounding the second cylindrical sleeve  24 B to ensure a sealing between the second cylindrical socket  14 B and the second cylindrical sleeve  24 B. 
     The sealing system  28  further comprises a rearward portion  32  surrounding the rear housing  25  of the second casing  26  to ensure a sealing between the inner housing  18  and the rear housing  25  of the second casing  26  when the first and second connectors  10  and  12  mate. 
     The sealing system  28  of the invention may be of a silicon material and as depicted in details on  FIGS. 6A-C , may be of one piece, the first and second frontward portions  30 A and  30 B extending side by side from and integrally with the rearward portion  32  along the mating axis X-X. The rear housing has preferably an external oval shape, the rearward portion  32  having thus a corresponding external contour of an oval shape. 
     At least one of the frontward portion and rearward portion of the sealing system  28  can be an axial compression seal with regard to the mating axis X-X as schematically illustrated on  FIG. 3A  or it can be a radial compression seal with regard to the mating axis X-X as schematically illustrated on  FIG. 3B  or it can be both an axial compression seal and a radial compression seal. By the term “axial compression seal” it is meant a sealing system in which the material, under a compression force parallel to the mating direction, deforms in a direction substantially perpendicular to the mating axis X-X. The term “radial compression seal” designates a sealing system for which the material, under a compression force perpendicular to the mating axis, deforms in a direction substantially parallel to mating axis X-X. 
     For example, each of the first and second frontward portions  30 A and  30 B comprises an external surface  33 A, respectively  33 B, provided with a cylindrical bulging  34 A, respectively  34 B adapted to be compressed radially against the inner surface  15 A and  15 B of the inner housing  18  when the first and second connectors  10  and  12  mate (see  FIG. 7 ). Each cylindrical bulging  34 A,  34 B comprises two inclined surfaces. 
     As best illustrated on  FIG. 6C  for the first frontward portion  30 A (but it is the same for the second frontward portion  30 B), the bulging  34 A comprises two inclined annular surfaces  36 A and  38 A joined on an annular apex  40 A. The apex  40 A has an external contour which has a greater size than any other external contour of the first frontward portion  30 A, such that it can be compressed when the first cylindrical sleeve  24 A is received in the corresponding first cylindrical socket  14 A (see  FIG. 7 ). Due to this geometrical configuration, the first frontward portion  30 A is compressed radially when the first and second connectors  10  and  12  mate. 
     A similar bulging  42  is provided on the external surface  33  of the rearward portion  32  adapted to be compressed against the inner surface  18 A of the inner housing  18  when the first and second connectors mate. Similarly to the bulging  34 A, the bulging  42  comprises two inclined annular surfaces  44  and  46  joined on an annular apex  48 , the external contour size of it being also greater than any external contour size of the external surface  33  of the rearward portion  32 . 
     As best illustrated on  FIG. 7 , the inner surface  18 A of the inner housing  18  extends partly in line (i.e. in continuity) with the inner surface  15 A and  15 B of the corresponding first and second cylindrical sockets  14 A and  14 B. Similarly, the rear housing  25  of the second casing  26  extends also partly in line with the first  24 A and second  24 B cylindrical sleeves. 
     The external surface of rearward portion  32  further comprises a transverse flat area  50  adapted to be compressed against the free end  14 ′A, respectively  14 ′B of the first  14 A and respectively second cylindrical socket  14 B when the first and second connectors  10  and  12  mate (see  FIG. 7 ). This flat area  50  connects the first and second frontward portions  30 A and  30 B together with the rearward portion  32 . 
     In order to avoid any risk of error when connecting the first and second connectors together, the second casing  26  is provided with a polarization lug  52  extending along the mating axis X-X between the first and second cylindrical sleeves  24 A and  24 B. The first casing  16  is accordingly provided with a positioning recess  54  able to receive the polarization lug  52  in one position only. 
     The polarization lug  52  extends from the rear housing  25  between the first and second cylindrical sleeves  24 A and  24 B and passes through the sealing system  28 . An opening  56 , through which the positioning lug  52  extends, is therefore provided on the flat area  50  of the sealing system  28  between the two frontward portions  30 A and  30 B. 
     When the first and second connectors  10  and  12  mate the sealing system  28  reduces the risk of water and/or dust intrusion in the connectors. More precisely, the first and second frontward portions  30 A and  30 B seal respectively and separately the first and second power terminal sleeves, whereas the rearward portion  32  seals the first and second connectors  10  and  12 . 
     As best seen on  FIGS. 5A and 5B , in order to secure the mating of the two connectors  10  and  12 , the second casing  26  may be provided with one or several connecting tongues  58  spread evenly on its external contour, forming connector retainers, and to be received within the annular space  22 , between the inner and the outer housings  18  and  20  of the first casing  16 . 
     In order to secure the sealing system  28  onto the second casing  26 , the rearward portion  32  is provided with one or several retention means adapted to cooperate with complementary retention means of the second casing to retain the sealing system  28  via the rearward portion  32  onto the second connector  12 . 
     More precisely, as illustrated on  FIGS. 6A-6C , four rear lugs  60  having a shape of hooks are located evenly at the rear part of rearward portion  32  and are designed to cooperate with a corresponding annular flange  62  provided on the second casing  26 . 
     As best illustrated on  FIG. 5B , the four retaining lugs  60  are distributed alternatively between the connecting tongues  58  of the second casing  26 . 
       FIGS. 8 ,  9 A- 9 C and  10 A- 10 C disclose another embodiment of a connector assembly having two power connectors. 
     The power contacts having a different size than those of the embodiment of  FIGS. 4 ,  5 A-B,  6 A-C and  7 , the first and second connectors  10  and  12  are slightly different. However, since they distinguish mostly only on their size, in order to avoid unnecessary repetition, only the important differences are mentioned below. 
     Actually, the first connector  10  is provided with a greater space between the first and second sockets  14 A and  14 B, consequently the positioning recess  54  is provided with two small lateral plates extending along the mating axis X-X. The polarization lug  52  is of a different shape compared with that of the embodiment of  FIGS. 4 ,  5 A-B,  6 A-C. The sealing member  28  differs essentially on its size and on the shape of the opening  56 . Actually, the opening  56  is greater and takes mostly all the place of the space available on the flat area  50  between the two frontward portions  30 A and  30 B, the curvature of the concave faces of the opening follow partly the contour of the two frontward portions  30 A and  30 B. 
     We will now describe an embodiment of a connector assembly having five power contacts, four of a similar size and a fifth one which is smaller. Connector assemblies having another number of power contacts, the power contacts being of the same or of different sizes are also part of the invention. 
     Referring to  FIGS. 11 ,  12 A-B and  13 A-C, the connector assembly comprises mainly the same elements and differs essentially from the above-mentioned connectors having two power contacts by the fact that it is provided with a different location of the power contacts. 
     The first connector  10  (see  FIG. 11 ) comprises a first cylindrical socket  14 A, a second one  14 B, a third one  14 C, a fourth one  14 D and a fifth one  14 E. The first, second, third and fourth cylindrical sockets  14 A- 14 D are preferably each of the same size and of the same shape, whereas the fifth cylindrical socket  14 E is smaller and of a different shape. More precisely, the first, second, third and fourth cylindrical sockets  14 A- 14 D are mostly of an oval external shape (viewed in cross-section perpendicular to the mating axis), whereas the fifth cylindrical socket  14 E is rather of a circular shape (viewed in cross-section section perpendicular to the mating axis). 
     The five cylindrical sockets may be joined one with at least one other. For instance, as illustrated, they are side by side and joined by pairs along the mating axis X-X. The fifth cylindrical socket  14 E is for instance located between the first, second and fourth cylindrical socket  14 A,  14 B and  14 D. 
     The second connector  12  (see  FIGS. 12A and 12B ) to be connected with the first connector  10  of  FIG. 11  comprises five corresponding cylindrical sleeves  24 A- 24 E. More precisely, the first, second, third and fourth cylindrical sleeves  24 A- 24 D are each of the same size and shape (i.e. oval), whereas the fifth cylindrical socket  24 E is smaller and has a circular shape. 
     The fifth cylindrical sleeve  24 E is, correspondingly to the fifth cylindrical socket  14 E, located between the first, second and fourth cylindrical sleeve  24 A,  24 B and  24 D. 
     The polarisation lug  52  may be located next to the second cylindrical socket  12 B. The opening  56  provided on the sealing member  28  for the polarization lug  52  is mostly of a rectangular shape and is located correspondingly on the flat area  50  next to the second cylindrical socket  12 B. 
     In order to secure the sealing system  28  onto the second casing  26  retainers, eight rear studs  60  terminating like an arrowhead are distributed evenly on the rear part of rearward portion  32  and are able to penetrate in corresponding holes  62  provided on the second casing  26 . 
     As above-described for the connector assembly having two pairs of power contacts, the sealing system and more precisely the external surfaces  33 A- 33 E of each frontward portion  30 A- 30 E and the external surface  33  of the rearward portion are provided with a correspondent bulging similar to those above-mentioned. 
     In order to avoid any risk of contacting the power contacts with one finger when a user mate the first and second connectors together, each of the cylindrical sockets and each of the cylindrical sleeves surrounds the power contacts according to the standard IP2X. 
     These connector assemblies are represented in relation to a special application (i.e. vehicles), but could be used in other applications. 
     In the embodiments illustrated, the connector assembly comprises a first connector  10  and a second connector  12  intended to mate with the first one. 
     As illustrated schematically on  FIG. 14  depicting a system, the first connector  10  may for example be carried by a base  64  of an automotive vehicle, whereas the second connector  12  may be carried by a power supply, more precisely a battery  66 . 
     It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. In particular, the invention is applicable to any kind of connectors, either electrical or optical. Further, although the description refers to connector assemblies for transmitting power, it is obviously transposable to connector assemblies that transfers signals