PATENT ABSTRACT
An electrical connector includes an insulative housing, at least one contact and at least one protecting insulator. The insulative housing defines a mating direction, a mating face and a receiving cavity recessed from the mating face along said mating direction. The at least one contact is received in the insulative housing and includes a contacting portion exposed into the receiving cavity, a retaining portion extending from one end of the contacting portion to be interferentially received in the insulative housing, and a forward end extending from the other end of the contacting portion to locate more closely to the mating face of the insulative housing than the contacting portion, and a connecting portion extending from the retaining portion to be exposed beyond the insulative housing. The protecting insulator entirely covers the forward end of the at least one contact.

PATENT DESCRIPTION
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an electrical connector and an electrical connector assembly, more particularly to an electrical connector and an electrical connector assembly for power transmission. 
         [0003]    2. Description of Related Art 
         [0004]    Electrical connectors are widely used today. In general, electrical connectors can be classified into personal use and industrial use. When in personal use, electrical connectors can be classified as desktop connectors, laptop connectors, mobile phone connectors, consuming connectors, and other types. When in industrial use, electrical connectors can be used in industrial computers, servers, and workstations. Power connector is one common kind of electrical connector used in different equipments. Usually, a plug-type power connector and a receptacle-type power connector mate with each other to supply power to the equipments. Contacts of the plug connector and the receptacle connector contact one another to form electrical connection. 
         [0005]    China Patent No. CN200820212432.9 disclosed a plug connector and a receptacle connector mating with each other for power transmission. The plug connector comprises a plug insulative housing and a plurality of plug contacts received in the plug insulative housing for power transmission. The plug insulative housing defines a receiving cavity for receiving the receptacle connector. The plug contact is of slice structure and extends into the receiving cavity for electrically connecting with the receptacle connector. Since the slice-shape plug contacts are exposed into the receiving cavity directly without any protection to contacting ends thereof, the contacting ends are prone to be contacted when in improper use status. Therefore, electric shock phenomenon has great possibility to be generated and the contacting ends are easy to be polluted or damaged. It is more serious when the connectors are used for high-power, high-voltage situations. 
         [0006]    Europe Patent No. EP1703597A1 disclosed a power connector comprising an insulative housing and a plurality of contacts assembled in the insulative housing. A one-piece retainer is assembled to the insulative housing and has protecting sections partially covering the front ends of contacting portions and upper and lower surfaces of the contacts. The retainer protects the contacting portions of the contacts from being touched unintendedly. Also, the protected contacting portions of the contacts also can avoid arc-discharge generation which is capable of influencing safe power transmission. The patent assures the contacts not to be touched from outside and also assures that the contacts not to be polluted or damaged for safe power transmission. However, the retainer is of one-piece structure and needs to align with all the contacting portions of the contacts before assembled to the insulative housing which adds the difficulty of assembly. Further, the contacting portions of the contacts are only partially covered by the retainer. The uncovered parts of the contacting portions of the contacts are still very close to the outside and easy to be polluted or damaged. Also, the one-piece structure has relative slim figure and insufficient strength which is not good enough. Further, when one contact is out of use, the whole retainer needs to be removed for repair which is not convenient enough. 
         [0007]    Hence, it is disable to design an electrical connector and an electrical connector assembly to address problems mentioned above. 
       BRIEF SUMMARY OF THE INVENTION 
       [0008]    Accordingly, an object of the present invention is to provide an electrical connector with improved protection means for providing reliable power transmission. 
         [0009]    Another object of the present invention is to provide an electrical connector assembly with improved protection means for providing reliable power transmission. 
         [0010]    In order to achieve the above-mentioned object, an electrical connector comprises an insulative housing, at least one contact and at least one protecting insulator. The insulative housing defines a mating direction, a mating face and a receiving cavity recessed from the mating face along said mating direction. The at least one contact is received in the insulative housing and comprises a contacting portion exposed into the receiving cavity, a retaining portion extending from one end of the contacting portion to be interferentially received in insulative housing, a forward end extending from the other end of the contacting portion to locate more closely to the mating face of the insulative housing than the contacting portion, and a connecting portion extending from the retaining portion to be exposed beyond the insulative housing. The protecting insulator entirely covers the forward end of the at least one contact. 
         [0011]    In order to achieve the above-mentioned object, an electrical connector assembly comprises a plug connector and a receptacle connector mating with the plug connector. The plug connector comprises a first insulative housing defining a mating face and a receiving cavity recessed along a mating direction from the mating face, at leas one first contact received in the first insulative housing, and at least one protecting insulator. The at least one first contact comprises a first contacting portion exposed in the receiving cavity, a first retaining portion extending from one end of the first contacting portion and retained in the first insulative housing, a forward end extending from the other end of the first contacting portion to be closer to the mating face than the first contacting portion. The at least one protecting insulator entirely covers the forward end of the at least one contact. The receptacle connector comprises a second insulative housing, and at least one second contact received in the second insulative housing. The at least one second contact comprises an elastic second contacting portion electrically connecting with the at least one first contact. The second insulative housing is received in the receiving cavity of the first insulative housing, and the elastic second contacting portion of the at least second contact slides along the protecting insulator then forms electrical connection with the first contacting portion of the at least one first contact. 
         [0012]    The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter, which form the subject of the claims of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
           [0014]      FIG. 1  is an assembled, perspective view of an electrical connector assembly in accordance with the first embodiment of the present invention, wherein a plug connector (electrical connector) and a receptacle connector (electrical connector) of the electrical connector assembly are in mating status; 
           [0015]      FIG. 2  is a view similar to  FIG. 1 , but viewed from a different aspect; 
           [0016]      FIG. 3  is a perspective view of the electrical connector assembly with the plug connector and the receptacle connector in separate status; 
           [0017]      FIG. 4  is a view similar to  FIG. 3 , but viewed from a different aspect; 
           [0018]      FIG. 5  is an exploded, perspective view of the plug connector in accordance with the first embodiment of the present invention; 
           [0019]      FIG. 6  is an exploded, perspective view of a first contact and a protecting insulator of the plug connector; 
           [0020]      FIG. 7  is an exploded, perspective view of the receptacle connector (electrical connector) in accordance with a first embodiment of the present invention; 
           [0021]      FIG. 8  is a cross-section view taken along line  8 - 8  of  FIG. 1 ; 
           [0022]      FIG. 9  is an assembled, perspective view of an electrical connector assembly in accordance with the second embodiment of the present invention; 
           [0023]      FIG. 10  is an exploded, perspective view of a plug connector in accordance with the second embodiment of the present invention; 
           [0024]      FIG. 11  is a view similar to  FIG. 10 , but viewed from a different aspect; 
           [0025]      FIG. 12  is a perspective view of an additional grounding contact of the plug connector; 
           [0026]      FIG. 13  is an assembled, perspective view of the plug connector in accordance with the second embodiment of the present invention; 
           [0027]      FIG. 14  is an exploded, perspective view of the receptacle connector in accordance with the second embodiment of the present invention; 
           [0028]      FIG. 15  is a view similar to  FIG. 14 , but viewed from a different aspect; 
           [0029]      FIG. 16  is an assembled, perspective view of  FIG. 15 ; and 
           [0030]      FIG. 17  is a cross-section view taken along line  17 - 17  of  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. In other instances, well-known circuits have been shown in block diagram form in order not to obscure the present invention in unnecessary detail. For the most part, details concerning timing considerations and the like have been omitted inasmuch as such details are not necessary to obtain a complete understanding of the present invention and are within the skills of persons of ordinary skill in the relevant art. 
         [0032]    Reference will be made to the drawing figures to describe the present invention in detail, wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by same or similar reference numeral through the several views and same or similar terminology. 
         [0033]    Referring to  FIGS. 1-4 , an electrical connector assembly  100  in accordance with the first embodiment of the present invention comprises a plug connector  10  and a receptacle connector  20  mating with each other. The plug connector  10  and the receptacle connector  20  are power connectors for power transmission in the preferred embodiment of the present invention, but the connectors are not only restricted to power type connectors. Also, the plug connector  10  and the receptacle connector  20  are the electrical connectors in accordance with the present invention. 
         [0034]    In the first embodiment of the present invention, the plug connector  10  comprises a first insulative housing  1 , a plurality of first contacts  2  attached to the first insulative housing  1 , and an additional grounding contact  4  also attached to the first insulative housing  1 . The receptacle connector  20  comprises a second insulative housing  6  and a plurality of second contacts  7  attached to the second insulative housing  6 . The first contacts  2  and the additional grounding contact  4  electrically connect with the second contacts  7  for power transmission. 
         [0035]    please refer to  FIGS. 1-2 ,  4 - 5  and  8 , the first insulative housing  1  defines a first mating face  11 , a receiving cavity  12  recessed rearward from the first mating face  11 , and a surrounding rib  13  enlarged from the circumferential edges of the receiving cavity  12 . The receiving cavity  12  is circumscribed by opposite top wall  111  and bottom wall  112 , a pair of opposite sidewalls  113 , and a rear wall  114 . The bottom wall  112  defines a rectangular recess  14  behind the surrounding rib  13 . A plurality of horizontal and vertical partition racks  115  extend into the receiving cavity  12  to divide the receiving cavity  12  into three first contact-receiving passageways  121  arranged in triangle relationship for receiving the first contacts  2  and penetrating through the rear wall  114 . The horizontal and vertical partition racks  115  connect with one another to assure that at least two adjacent sides of each first contact  2  are surrounded by the partition racks  115 . 
         [0036]    Please refer to  FIGS. 5-6  and  8 , the first contacts  2  are three power contacts arranged in triangle relationship and received in the first contact-receiving passageways  121 . The two first contacts  2  aligning with each other and arranged on the same horizontal line are a positive contact and a negative contact in power transmission. The first contact  2  located at the top of the triangle is a grounding contact in power transmission. Each first contact  2  is of straight shape with a certain height and comprises a first retaining portion  21  interferentially engaged with the rear wall  114  of the first insulative housing  1 , a first connecting portion  22  extending rearward from the first retaining portion  21  to be exposed beyond the rear wall  114  for electrically connecting with wires (not shown), a flat first contacting portion  23  extending forward from the first retaining portion  21 , and a forward end  24  extending forward from the first contacting portion  23  ( FIG. 6 ). The forward end  24  is shrunk from the first contacting portion  23  with width and thickness both smaller that those of the first contacting portion  23 . The first contacting portion  23  has a contacting surface  231  behind the forward end  24 . When the first contacts  2  are retained in the first insulative housing  1 , the contacting portions  23  and the forward ends  24  are all exposed in the receiving cavity  12 , the connecting portions  22  extend beyond the rear wall  114 . The forward end  24  ha a front face  241  close to the first mating face  11  and an extending face  242  located at the same side as that of the contacting surface  231 . 
         [0037]    Since the forward ends  24  are located closer to the first mating face  11 , the forward ends  24  are easier to be touched by fingers or other things, or covered by dust from outside, all cause the forward ends  24  (especially the front faces  241  thereof) are prone to be polluted or damaged, further influence the stability of power transmission or raise unsafe problems. Please refer to  FIGS. 5 and 6 , a protecting insulator  3  is overmolded with the forward end  24  of the first contact  2  in the preferred embodiment of the present invention which protects the forward end  24  from the problems described above. Of course, in an alternative embodiment, the protecting insulators  3  also can be assembled to the forward ends  24  of the first contacts  2 . The protecting insulator  3  is a hollow cuboid with one open end toward the forward end  24  of the first contact  2 . The protecting insulator  3  comprises a front end portion  31  covering the front face  241  of the forward end  24  and a cover portion  32  extending rearward from the end portion  31  to cover the extending faces  242 . Therefore, the insulated area is extended into inner section of the receiving cavity  12  which protects the contacting portion  23  from being polluted or damaged. The problems addressed above are solved to assure stability of power transmission and safety. 
         [0038]    In addition, the outer surface  321  of the cover portion  32  is coplanar with the contacting surface  231  for assuring the stability of the second contact  7  of the receptacle connector  20  sliding along the outer surface  321  and the contacting surface  231 . 
         [0039]    Please refer to  FIGS. 5 and 8 , the additional grounding contact  4  is longitudinal and located below the grounding first contact  2  and together received in the same first contact-receiving passageway  121  with the grounding first contact  2 . The additional grounding contact  4  comprises an additional retaining portion  41  retained in the first insulative housing  2 , an additional connecting portion  42  extending rearward from the additional retaining portion  41  and beyond the first insulative housing  2 , and an additional contacting portion  43  extending forward from the additional retaining portion  41  and forming a contacting end  430  curved upward slightly. The contacting end  430  is located below a front section of the outer surface  321  of the protecting insulator  3  to assure that the additional grounding contact  4  electrically contacts the grounding second contact  7  of the receptacle connector  20  after the grounding first contact  2 . That means, the additional grounding contact  4  and the grounding first contact  2  form electrical connection with the same grounding second contact  7 . Thus, the additional grounding contact  4  is a spare grounding contact to assure an always grounding function even when the grounding first contact  2  is invalid. The grounding function is very important for high-power, high-voltage power connectors. 
         [0040]    Please refer to FIGS.  2  and  7 - 8 , the second insulative housing  6  comprises a second mating face  61  and a plurality of second contact-receiving passageways  60  recessed forward from the second mating face  61 . A protection block  62  protrudes upward from a bottom surface of each second contact-receiving passageway  60  and extends forward from the second mating face  60  into the second contact-receiving passageway  60  a certain distance. In  FIGS. 2 and 8 , a latch arm  63  is disposed at a bottom of the second insulative housing  6  for latching with the recess  14  of the first insulative housing  1 . The latch arm  63  comprises a latch section  631  and a pressing section  632  respectively at opposite ends of the latch arm  63 . 
         [0041]    The second contact  7  comprises a flat second retaining portion  71  retained in the second insulative housing  6 , an elastic second contacting portion  72  extending rearward from the second retaining portion  71  and bending upwardly slightly, and a second connecting portion  74  extending forward from the second retaining portion  71  beyond the second insulative housing  6  for electrically connecting with wires (not shown). The second contacting portion  72  comprises an elastic contacting free end  73  with certain deformation ability. In  FIG. 8 , when the second contacts  7  are retained in the second insulative housing  6 , the elastic second contacting portions  72  extend beyond upper surfaces of the protection blocks  62 . While, when the plug connector  10  and the receptacle connector  20  mate with each other, the elastic second contacting portions  72  are compressed by the contacting surfaces  231  of the second contacts  2 . The free ends  73  are compressed to be below the upper surfaces of the protection blocks  62 , thus, the second contacts  7  are prevented from being touched or damaged by outside. Correspondingly, the second contacts  7  also comprise three power contacts in triangle relationship in the preferred embodiment of the present invention, a positive second contact, a negative second contact and a grounding second contact  7  located at the top point of the triangle. Of course, the three second contact-receiving passageways  60  are also arranged in triangle relationship with the top second contact-receiving passageway  60  defines an additional contact-receiving passageway  65  at the bottom thereof to protrude through the protection block  62 . 
         [0042]    Please refer to  FIG. 8 , when the plug connector  10  mates with the receptacle connector  20 , the second insulative housing  6  is received in the receiving cavity  12  of the first insulative housing  1 . The protection blocks  62  guide the first contacts  2  into the second contact-receiving passageways  60  to form electrical connection with the second contacts  7 . During the mating process, the elastic second contacting portion  72  slides along the outer surface  321  of the cover portion  32  firstly and then slide beyond the cover portion  32  to finally form electrical connection with the contacting surface  231  of the first contacting portion  23 . At the same time, the latch section  631  of the latch arm  63 ′ protrudes into the recess  14  of the first insulative housing  1  to improve the retention force between the plug connector  10  and the receptacle connector  20 . The additional grounding contact  4  protrudes through the additional contact-receiving passageway  65  to contact the grounding second contact  7  after the grounding first contact  2  contacts the grounding second contact  7 . 
         [0043]    When need to separate the plug connector  10  and the receptacle connector  20 , user just needs to press the pressing section  632  of the latch arm  63  downward, the latch section  631  is caused to be separated from the recess  14 . In alternative embodiments, the latch arm  63  also can be disposed on the first insulative housing  1  of the plug connector  10  and the recess  14  is defined in the second insulative housing  6  which also can realize the same purpose. The first contacts  2  can be assembled to or insert-molded with the first insulative housing  1 , and the second contacts  7  also can be assembled to or insert-molded with the second insulative housing  6 . In addition, the additional grounding contact  4  also can be disposed in the second insulative housing  6  of the receptacle connector  20  after a skilled person in the art makes some simple changes to the second insulative housing  6 . 
         [0044]      FIGS. 9-17  disclose a second embodiment of the present invention, a plug connector  10 ′ and a receptacle connector  20 ′ of an electrical connector assembly  100 ′ have similar designs as described in the first embodiment. Hence, only differences will be introduced hereinafter. 
         [0045]    Compared with the plug connector  10 , the plug connector  10 ′ has different first contact structure. The first contacts  2 ′ have different first connecting portions  22 ′ which bend upward (for grounding first contact  2 ′) and downward (for power first contacts  2 ′). The plug connector  10 ′ also comprises a first retainer  5 ′ insert-molded with the first contacts  2 ′ together to form a first contact module. The protecting insulators  3 ′ are firstly insert-molded with the forward ends  24 ′ of the first contacts  2 ′, then the first retainer  5 ′ is insert-molded with the first contacts  2  and together assembled to the first insulative housing  1 ′. The first retainer  5 ′ is assembled to a rear end of the first insulative housing  1 ′ and has a pair of latch means  51 ′ on opposite lateral sides thereof to latch into a pair of through holes  117 ′ of locking means  116 ′ of the first insulative housing  1 ′. An L-shape cutout  52 ′ is recessed downward from a top edge of the first retainer  5 ′ for penetration of the additional grounding contact  4 ′. The first insulative housing  1 ′ defines an additional contact-receiving passageway  122 ′ with a front end thereof communicating with the top first contact-receiving passageway  121 ′. 
         [0046]    The additional grounding contact  4 ′ comprises an additional retaining portion  41 ′, a flat additional contacting portion  43 ′ extending forward from the additional retaining portion  41 ′, and an additional connecting portion  42 ′ extending rearward from the additional retaining portion  41 ′. The additional contacting portion  43 ′ penetrates through the additional contact-receiving passageway  122 ′ to be exposed in the top first contact-receiving passageway  121 ′ together with the grounding first contact  2 ′. A contacting end  430 ′ is stamped with a bump to electrically contact the grounding second contact  7 ′ of the receptacle connector  20 ′. The additional retaining portion  41 ′ comprises a main portion  412 ′ located in a horizontal surface and a rib  411 ′ extending vertically from one edge of the main portion  412 ′ to locate in a vertical surface. A plurality of first barbs  410 ′ and a plurality of second barbs  413 ′ are respectively formed at rear ends of the main portion  412 ′ and the rib  411 ′ to interferentially engage with inner walls of the additional contact-receiving passageways  122 ′ for retaining the additional grounding contact  4 ′ in the first insulative housing  1 ′. The additional connecting portion  42 ′ comprises an L-shape extended section  421 ′ mainly located in a horizontal surface and extending from the additional retaining portion  41 ′, and a connecting section  422 ′ bending upwardly from the extended section  421 ′. 
         [0047]      FIGS. 14-16  disclose the receptacle connector  20 ′. Compared with the receptacle connector  20 , the receptacle connector  20 ′ further comprises a second retainer  9 ′ retaining the second contacts  7 ′ together with the second insulative housing  6 ′. The second retainer  9 ′ is assembled to the second insulative housing  6 ′ after the second contacts  7 ′ are assembled to be received in the second contact-receiving passageways  60 ′ of the second insulative housing  6 ′. The second contacts  7 ′ are sandwiched between the second retainer  9 ′ and the second insulative housing  6 ′ to provide better support to the second connecting portions  74 ′. The second retainer  9 ′ forms a pair of latch means  95 ′ on opposite lateral sides to lock into through holes  66 ′ of a pair of locking means  64 ′ of the second insulative housing  6 ′ to attach the second retainer  9 ′ tightly to the second insulative housing  6 ′. Further, the second contacting portion  71 ′ is of bifurcated shape to improve elasticity thereof. 
         [0048]    Since the plug connector  10 ,  10 ′ and the receptacle connector  20 ,  20 ′ are high-power power connectors, heat radiation issue must be considered. In the second embodiment of the present invention, heat-radiation structures are designed. The first insulative housing  1 ′ defines a plurality of heat-radiating holes  17 ′ to communicate with at least one first contact-receiving passageway  121 ′, while, the second insulative housing  6 ′ defines a plurality of heat-radiating holes  67 ′ to communicate with at least one second contact-receiving passageway  60 ′. In addition, the second retainer  9 ′ also defines a plurality of heat-radiating passages  97 ′ to communicate with at least one second contact-receiving passageway  60 ′. These heat-radiating structures  17 ′,  67 ′ and  97 ′ communicate the first and second contact-receiving passageways  121 ′,  60 ′ with outside to radiate heat generated by mated first and second contacts  2 ′,  7 ′ to the outside in time to satisfy the heat-radiating requirement. 
         [0049]    It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. For example, the tongue portion is extended in its length or is arranged on a reverse side thereof opposite to the supporting side with other contacts but still holding the contacts with an arrangement indicated by the broad general meaning of the terms in which the appended claims are expressed.