Abstract:
A socket for a plug connection comprises a socket housing that has a contact chamber in which a plurality of socket contacts is arranged, a protective seal being provided which can be moved between a covering position in which it closes the contact chamber so as to be essentially flush towards outside, and a contact position in which the socket contacts are able to be accessed, the protective seal being able to be transferred from the covering position into the contact position by means of a complementary plug. There is further proposed a plug connection including such socket and a plug.

Description:
TECHNICAL FIELD  
         [0001]    The invention relates to a socket for a plug connection, comprising a socket housing that has a contact chamber in which a plurality of socket contacts is arranged.  
         BACKGROUND OF THE INVENTION  
         [0002]    Such a socket is known from DE 198 09 801 A1. The plug connection formed by such socket together with a complementary plug is suitable for being employed, in particular, in motor vehicles e.g. in the region of the doors or the bottom. In order to prevent any ingress of contamination into the socket, there is provided a plunger which is shiftably mounted inside the housing and closes the contact chamber of the socket in case the plug is not plugged in.  
           [0003]    The invention is based on the object to further develop a socket of the type initially mentioned in that an improved protection against the ingress of contaminations is ensured, so that the plug connection can also be used in the bottom region of the motor vehicle, which is particularly exposed to contaminations.  
         BRIEF SUMMARY OF THE INVENTION  
         [0004]    According to the invention, a socket for a plug connection comprises a socket housing that has a contact chamber in which a plurality of socket contacts is arranged, a protective seal being provided which can be moved between a covering position in which it closes the contact chamber so as to be essentially flush towards outside, and a contact position in which the socket contacts are able to be accessed, the protective seal being able to be transferred from the covering position into the contact position by means of a complementary plug. The protective seal reliably prevents any ingress of contaminations into the contact chamber, whilst at the same time a simple and safe connection between the plug and the socket is made possible. Prospective contaminations do not accumulate over the contact chamber, because the protective seal covers the outer side of the contact chamber so as to be flush with it. Moreover, prospective contaminations can easily be removed.  
           [0005]    In a preferred embodiment, the protective seal rests at the edge of the opening of the contact chamber, the edge being configured skewed. This results in an automatic centering of the protective seal to its optimum position. In addition, the pressure that is exerted on the protective seal from outside causes the protective seal to come to rest at the skewed edge more firmly, which automatically improves the sealing effect.  
           [0006]    In case the protective seal consists of an elastic material, then a particularly good sealing function is achieved, because the protective seal can have a snug fit with the opening of the contact chamber.  
           [0007]    It is particularly of advantage if the protective seal is mounted to a plunger that is shiftably mounted in the socket housing. In this way it is ensured that the protective seal together with the plunger can be pushed into the socket when the plug is inserted into the socket. In so doing, the socket contacts are freed only so far as the plug is inserted into the socket housing. Hence, the sealing function will be maintained for that part of the socket housing that is not yet applied by the plug.  
           [0008]    The plunger is preferably provided with a surrounding groove that is engaged by a sealing skirt formed on the protective seal. It is in this way that the elastic protective seal can be fixed to the plunger with minimum expenditure.  
           [0009]    According to the preferred embodiment it is provided for that the plunger is provided with a deepening on its end face facing the plug, that the protective seal extends across the end face of the plunger and projects towards outside beyond the side surfaces of the plunger in the covering position, and in that the protective seal comes to rest at the side surfaces of the plunger if it is pressed into the deepening by the plug, so that the plunger can be pushed into the contact chamber without the protective seal touching the socket contacts. Upon inserting the plug, the protective seal will thus automatically retract into its contact position, so that the plug can be lowered into the contact chamber without the protective seal rubbing against the edge of the contact chamber and without contaminations—that could adhere to the protective seal—being taken off and possibly getting in this way into the contact chamber.  
           [0010]    It can be further provided for that the socket contacts are receded with respect to that edge of the socket housing which faces the plug. Thereby it is ensured that the socket contacts can not be contaminated by contaminations which possibly adhere to the protective seal.  
           [0011]    In the plug connection according to the invention, there is provided a plug including a plug housing in which a plurality of plug contacts is arranged, it being provided that a protective shield mounted to the plug is movable between a covering position in which it covers the plug contacts, and a contact position in which the plug contacts are able to be accessed, the protective shield being able to be transferred from the covering position into the contact position during inserting into the socket. A mechanical damage or a contamination is prevented by the protective shield. This is of importance if the plug, for instance, is mounted to a vehicle seat which can be removed from the vehicle. The protective shield prevents the plug contacts from being deformed or damaged in any other way during the handling of the removed vehicle seat, because that could prevent a reliable contacting of the socket mounted to the vehicle bottom when the seat has been installed again.  
           [0012]    It is a particularly advantageous arrangement if the plug comprises a plug-in section at which the plug contacts are exposed and which can be plugged into the socket, and if the protective shield surrounds the plug-in section on all sides. This is furthermore particularly of advantage if the protective shield comprises a skirt at its end associated to the front end of the plug-in section, by means of which skirt the plug contacts are forced inwards during inserting into the socket, so that they do not touch the edge of the contact chamber of the socket. Thereby it is prevented that any contaminations present at the edge of the contact chamber of the socket are taken up by the plug contacts and are introduced into the contact chamber. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 shows an exploded view of the plug;  
         [0014]    [0014]FIG. 2 shows an exploded view of the socket;  
         [0015]    [0015]FIG. 3 shows a cross-sectional view through the plug of FIG. 1;  
         [0016]    [0016]FIG. 4 shows a cross-sectional view through the socket of FIG. 2;  
         [0017]    [0017]FIG. 5 shows a perspective sectional view of the plug of FIG. 1;  
         [0018]    [0018]FIG. 6 shows a perspective sectional view of the socket of FIG. 2;  
         [0019]    [0019]FIG. 7 shows a cross-sectional view corresponding to FIGS. 3 and 4, with the plug plugged into the socket;  
         [0020]    [0020]FIG. 8 shows a perspective sectional view corresponding to FIGS. 6 and 7, with the plug plugged into the socket; and  
         [0021]    [0021]FIG. 9 shows a further perspective sectional view of plug and socket in the state plugged into each other. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]    In FIGS. 1, 3 and  5  there is shown a plug  10  which comprises a plug housing  11  including a plug-in section  12 , a plug flange  14 , two plug springs  16 , a protective shield  18  including a skirt  18   a,  plug contacts  20  and a plug cover  22  including contact cut-outs  22   a.    
         [0023]    The plug-in section  12  of the plug housing  11  is configured like a piston and is provided with a protrusion  12   a  at its front end as seen in the plug-in direction. The plug contacts are arranged in receptacles in the plug housing  11  so as to be unsupported, they being bent and configured with an apex  13 . The plug contacts  20  come out of the plug through the contact cut-outs  22   a  of the plug cover  22  with respect to the Figures in upward direction, so that they can be connected to cables. The plug cover  22  closes the plug-in section  12  towards the top.  
         [0024]    The protective shield  18  is shiftably mounted to the plug housing  11  and is shown in FIGS. 1, 3 and  5  in the covering position. The covering position is defined in that a shield flange  18   b  of the protective shield  18  rests at the plug flange  14  of the plug housing  11 . In the covering position, the exposed region of the plug contacts in the plug-in section  12  is covered, so that the plug contacts are protected from mechanical damage and from contamination, too. Here, the skirt  18   a  rests at the plug-in section  12  with a tight fit. The protective shield  18  can be brought from the covering position against the action of the plug springs  16  and contrary to the plug-in direction of the plug into the socket, i.e. upwards with respect to the Figures, into a contact position in which the plug contacts  20  are exposed in the region of the plug-in section  12 .  
         [0025]    In FIGS. 2, 4 and  6  there is shown a socket  23  into which the plug  10  can be plugged. The socket  23  has a housing which is formed by a socket flange  24  as well as first and second contact chamber sections  34 ,  36 . The two contact chamber sections  34 ,  36  form a contact chamber  37  in which a plurality of socket contacts  30  as well as a plunger  28  are arranged. The opening to the contact chamber is formed by an edge  24   a  in the socket flange  24 . The socket contacts  30  are configured such that their end sections located in the vicinity of the socket flange  24  are receded towards outside with respect to the edge  24   a  of the socket flange (see FIG. 8). The socket contacts  30  project out of the contact chamber at the lower end of the second contact chamber section  36  with respect to the Figures, so that a cable can be connected.  
         [0026]    At its end associated to the edge  24   a,  the plunger  28  has a surrounding groove  28   a  as well as a deepening  28   b,  the transition from the end face of the plunger to the groove  28   a  being configured skewed. A protective seal  26  extends across the deepening and has a middle section  26   a  as well as a surrounding sealing skirt  26   b  which engages the groove  28   a,  so that the protective seal is held on the front end of the plunger. In the position shown in FIGS. 2, 4 and  6 , the protective seal  26  is in its sealing position in which the middle section  26   a  is flat and it tightly rests at the edge  24   a  of the socket. As seen from the outside of the socket, the protective seal  26  has the same shape as the opening to the contact chamber  37 . In the relaxed state, the protective seal  26  has slightly larger dimensions than the opening in the socket flange  24 , so that the protective seal rests at the edge  24   a  in a biased fashion.  
         [0027]    Arranged in the contact chamber are two socket springs  32  on one spring guide element  38  each. The socket springs urge the plunger  28  into the position shown in FIGS. 2, 4 and  6 , in which the protective seal  26  rests at the skewed edge  24   a  of the contact chamber  37 . In this arrangement, the protective seal  26  terminates flush with the socket flange  24  towards outside. Thus, in the covering position which is shown here, the contact chamber  37  is closed against external influences such as dirt and wetness.  
         [0028]    The operation of plugging the plug  10  into the socket  23  will be described in detail in the following. When the plug  10  is placed on the socket  23 , first the protrusion  12   a  is pressed against the protective seal  26 . Thereby, the protective seal is forced into the deepening  28   b  on the end face of the plunger  28  until it rests at the bottom thereof. In so doing, the middle section  26   a  of the protective seal  26  “shortens”, so that its outer edge retracts from the edge  24   a  of the socket flange  24  and is pulled towards the skew of the plunger between the end face thereof and the groove  28   a.  If the protective seal  26  is in this contact position, the plunger  28  can be pushed into the contact chamber  37  without the protective seal touching the edge  24   a  of the socket flange  24 . In this way it is prevented that contaminations which are possibly present on the outside of the socket  23  or the protective seal  26  are transferred to the socket contacts  30 . In addition, contaminations are not transferred to the socket contacts either, because these are receded.  
         [0029]    During inserting the plug-in section  12  into the opening of the socket flange  24  or into the first contact chamber section  34 , the plunger  28  is pushed further down against the spring force of the socket springs  32 . As the protective shield  18  rests at the outer side of the socket flange  24 , it is pushed back in the process, so that the plug contacts  20  are gradually exposed and are pushed into the contact chamber  37 . In so doing, they are not exposed at any point in time, so that they are always protected from external influences during the entire plug-in operation. During the plug-in operation, the skirt  18   a  forces the bent plug contacts  30  towards inside into the plug-in section  12  when it slips over the apex  13 , so that the plug contacts enter into the contact chamber  37  of the socket without touching the edge  24   a.    
         [0030]    Now, the plug-in section  12  can be pushed into the first contact chamber section  34  as far as until a projection  12   b  of the plug housing  11  rests at the skirt  18   a  and the plug flange  14  tightly rests on the socket flange  24 , whereby a good sealing effect is ensured (see FIGS. 7, 8 and  9 ). In this process, the protective shield  18  is completely pushed back to the contact position. The plug-in section  12 , the plug contacts  20  and the socket contacts  30  are dimensioned such that the plug contacts make full electrical contact with the socket contacts at the end of the plug-in procedure. It is achieved in particular by the engagement of the protrusion  12   a  in the deepening  28   b  that the plug-in section  12  is centered; with this, the plug contacts  20  and the socket contacts  30  have good contact with each other both on the left and right hand-side with respect to the Figures.  
         [0031]    When the plug  10  including the plug-in section  12  is retracted from the first contact chamber section  34  of the socket  23 , there will be maintained at any time, due to the spring force of the socket springs  32 , a tight contact between the plug-in section and the plunger  28  in the region of the protrusion  12   a  and the deepening  28   b.  At the same time the protective shield  18  continues to rest at the socket flange  24 . When the plug  10  is completely pulled out of the socket  23 , the protective shield  18  returns to its covering position in which the plug contacts  20  are protected from external influences. At the same time the protective seal  26  returns to its covering position in which it tightly rests at the edge  24   a  of the socket flange  24  and closes the contact chamber  37  of the socket.