Abstract:
A plug is provided for producing an electrical connection with a plug module, such as a wiring harness plug for creating an electrical connection with a control device in a motor vehicle. The plug includes a plug body that has a multiplicity of channels for accommodating electrical lines; a mat seal that has a multiplicity of channels for guiding electrical lines accommodated in the channels of the plug body and that is situated on the at least one laterally circumferential radial seal in order to seal the plug; and a pressure plate that has a multiplicity of channels for guiding electrical lines accommodated in the channels of the plug body.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a plug for producing an electrical connection with a plug module, such as a wiring harness plug for a control unit in a motor vehicle. 
     BACKGROUND OF THE INVENTION 
     In a vehicle, in the engine compartment and in the body compartment numerous electrical and electronic control devices are installed that have to be electrically connected to one another and to further components of the vehicle such as sensors and actuators. 
     For this purpose, a control device can be equipped with a plug module on whose multipoint connector there may be situated a few hundred electrical contacts, for example for power supply and for a transmission of signals. A corresponding plug connected to a wiring harness can be plugged onto the plug module in order to create the electrical connection. 
     In order to protect the electrical contacts of the plug and the plug module against what may include aggressive media and deposits in the engine compartment, plugs for control devices are produced from a plurality of individual components and are equipped for example with sealing mats, or mat seals. At the edges of these mat seals, there may be attached radial seals, for example in the form of sealing lips, which are realized for the purpose of sealing the plug and protecting the electrical contacts. 
     However, tightness problems have been observed in plugs, in particular after being connected and disconnected numerous times, which can lead for example to shortened lifespans of the plug connectors and/or to malfunctioning. 
     SUMMARY 
     Specific embodiments of the present invention advantageously make it possible to provide a plug for a wiring harness of a vehicle in a tight-sealing embodiment that increases the lifespan of the plug connection, improves sealing tightness, and/or can be produced in a simplified production process. 
     According to a specific embodiment of the present invention, the plug has a plug body that has a multiplicity of channels for accommodating electrical lines. In addition, the plug has a mat seal that has a multiplicity of channels for guiding the electrical lines accommodated in the channels of the plug body, and on which at least one laterally circumferential radial seal is situated in order to seal the plug. In addition, the plug has a pressure plate that has a multiplicity of channels for guiding the electrical lines accommodated in the channels of the plug body. 
     The mat seal and the pressure plate can be placed into a receptacle region of the plug body so that the channels of the pressure plate, of the mat seal, and of the plug body each open into one another and form continuous channels for accommodating the electrical lines. Here, the channels define an axial direction of the plug. 
     The receptacle region of the plug body has a boundary that annularly surrounds the mat seal and the pressure plate, so that the radial seal of the mat seal is situated between the boundary of the receptacle region and the mat seal. 
     Overall, the plug can be realized so as to provide an electrical connection between a wiring harness and a control unit that is long-lived and reliable due to the tight-sealing construction of the plug. 
     For this purpose, the pressure plate and the mat seal are fashioned so as to cooperate with one another such that when the mat seal and the pressure plate are placed into the receptacle region of the plug body through a displacement of the pressure plate in the axial direction an edge region of the mat seal is spread in a radial direction so that the radial seal of the mat seal is pressed against the boundary of the receptacle region, radially sealing the plug. Here, the radial direction runs orthogonal to the axial direction. 
     Ideas for specific embodiments of the present invention can be regarded as being based on the observations described below: up to now, as a rule a relatively large force has had to be applied in order to place the mat seal into the receptacle region of the plug body, because the radial seal is pressed in sealing fashion against the boundary of the receptacle region of the plug body already during placement of the mat seal. The high plugging forces of the mat seal sometimes have the result that during mounting of the plug the radial seal is damaged, for example crushed, torn, or shorn away. As a result, sealing problems are observed in plugs, so that the electrical contacts inside the plug are no longer adequately protected. 
     Through the cooperating realization according to the present invention of the pressure plate and the mat seal, it can be ensured that the radial seal of the mat seal can no longer be damaged during assembly of the plug, because the radial seal is not pressed against the boundary of the receptacle region until the pressure plate is placed into the receptacle region of the plug body. In this way, a sealing function of the mat seal can be ensured and the mounting of the mat seal is advantageously simplified, because the mat seal can be mounted in the plug body in sealing fashion with a low exertion of force. 
     According to a specific embodiment of the present invention, the edge region of the mat seal, which is spread by the displacement of the pressure plate, is fashioned at least in a partial area as an inclined surface that inclines up to the boundary of the receptacle region of the plug body. The inclined surface is fashioned so as to introduce a force acting in the radial direction into the edge region of the mat seal upon displacement of the pressure plate in the axial direction, so that the edge region can be pressed against the plug body, in particular against the boundary of the receptacle region. 
     According to a specific embodiment of the present invention, the pressure plate has an edge region that is fashioned, as a press-on surface, so as to cooperate with the inclined surface of the edge region of the mat seal, and has, at least in a partial area, an incline differing from the inclined surface of the mat seal. 
     In this way, it can be ensured that the edge region of the mat seal can be spread by the edge region of the pressure plate and can be pressed with the radial seal against the boundary of the receptacle region of the plug body, so that the radial seal of the mat seal seals the plug in the radial direction. 
     According to a specific embodiment of the present invention, the mat seal has at least two radial seals for sealing the plug that are situated between the boundary of the receptacle region of the plug body and the mat seal, one of the radial seals being fashioned in such a way that when the mat seal is placed into the receptacle region of the plug body it is pressed against the boundary of the receptacle region, holding the mat seal in a position. 
     Through the holding of the mat seal at the provided position, the mounting of the plug can be made easier and the sealing function of the mat seal can be ensured. In addition, in this way it can be ensured that the channels of the mat seal, of the pressure plate, and of the plug body open into one another, so that the electrical lines can be guided through the channels in sealing fashion. Due to the fact that only one radial seal is pressed radially into the receptacle region of the plug body during the mounting of the mat seal, and the second radial seal is not pressed radially against the receptacle region until the pressure plate is mounted, in addition damage to the radial seals resulting from the mounting can be avoided. This can also result in a savings of production costs, because there will be fewer rejected mat seals. 
     According to a specific embodiment of the present invention, the mat seal is fashioned asymmetrically with regard to a side facing the pressure plate and a side facing away from the pressure plate. In other words, the mat seal is not symmetrical relative to a plane normal to the axial direction; i.e., it is fashioned asymmetrically in the axial direction. 
     The idea of the asymmetrical embodiment of the mat seal can be regarded as being based on the following described observations: the channels in the mat seal used for the guidance of lines can be situated at various positions in the mat seal. Here, the channels are often not distributed uniformly; i.e. in particular they can be situated asymmetrically in the mat seal. Up to now, mat seals have in general been fashioned symmetrically with regard to their external contour, for which reason they have to be sorted during production because otherwise there is a danger that a mat seal will be mounted so as to be reversed with regard to its sides. A mat seal mounted in side-reversed fashion can however result in an untight plug, which can reduce the reliability and lifespan of the plug connection. 
     Through the asymmetrical embodiment of the mat seal according to the present invention, it can be advantageously ensured that during production of the plug the correct installation position of the mat seal can be recognized, for example by hand or by a robot. This can result in a further reduction in production costs, because on the one hand a sorting of the mat seal can be omitted, and on the other hand the number of plugs rejected as untight can be reduced. 
     According to a specific embodiment of the present invention, a circumference of the mat seal on the side facing the pressure plate is larger than on the side facing away from the pressure plate. This can facilitate placement of the mat seal into the receptacle region of the plug body, because the mat seal can easily be placed in the provided position. In addition, in this way the sealing of the plug can additionally be ensured because the radial seal, already pressed against the boundary of the plug body during placement of the mat seal, can be pressed securely onto the boundary of the receptacle region without being damaged during this operation, due to the correct installation position of the mat seal. Thus, in addition the rejection of untight plugs in production, and therewith the production costs, can be further reduced. 
     According to a specific embodiment of the present invention, the mat seal has a sealing body on the side facing away from the pressure plate. The sealing body can for example be made of an elastic material applied flatly on the side of the mat seal facing away from the pressure plate, or can for example be realized as an element running circumferentially around the axial direction. That is, the sealing body can for example be realized in the form of a surface seal, or can cover only a partial area of the side of the mat seal facing away from the pressure plate. In addition, the mat seal can be fashioned in one piece with the sealing body, or the sealing body can be fashioned as a separate component, for example in the form of a mat having corresponding channels for guiding the electrical lines. 
     According to a specific embodiment of the present invention, the sealing body of the mat seal is fashioned so as to be pressed against the plug body in the axial direction during the displacement of the pressure plate in the axial direction, thus sealing the plug in the axial direction. In this way, the plug can advantageously additionally be sealed in the axial direction without requiring further production costs. 
     According to a specific embodiment of the present invention, the sealing body and/or the circumferential radial seals of the mat seal are made of a silicone material. As a soft and tough material, silicone can advantageously be suitable for this purpose, because it can be exposed to high pressure loads and tensile forces without tearing or being damaged. However, other elastic sealing materials, such as Viton, can also be used as radial seals and sealing bodies. 
     An aspect of the present invention relates to a plug system having a plug and a plug module that accepts the plug. The plug system can for example be used to produce an electrical connection between a wiring harness and a control device in a motor vehicle. Here, the plug module can be attached to the control device and the plug can be connected to the wiring harness of the vehicle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a perspective view of a plug according to a specific embodiment of the present invention. 
         FIG. 2  shows a perspective view of a part of the plug of  FIG. 1 . 
         FIG. 3  shows an exploded view of the part of the plug of  FIG. 2 . 
         FIG. 4  shows a cross-section through a plug system according to a specific embodiment of the present invention. 
         FIG. 5  shows a perspective view of a mat seal according to a specific embodiment of the present invention. 
         FIG. 6  shows a side view of the mat seal of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a plug  10  having a plug cover  11 , a plug lever  13 , and a plug body  12 . Plug body  12  has a plug base  14  that can be plugged onto plug module  25  in order to produce an electrical connection with a plug module  25  (see  FIG. 4 ). Plug cover  11  has a receptacle opening  15  via which electrical lines of a wiring harness can be guided into plug body  12 . 
     Plug lever  13  surrounds plug body  12  in a U shape with two arms  17 , on each of whose ends there is situated a shaft  19 . The two shafts  19  are received on two opposite sides of plug base  14 . Arms  17  are connected to a cross-beam  21  in which a plug lock  23  is attached. 
     Plug lever  13  is fashioned so as to be moved from a starting position to an end position and at the same time to pull plug  10  into plug module  25 . In  FIG. 1 , plug lever  13  is shown in the end position, plug lock  23  for securing the electrical connection being locked to plug module  25 . 
       FIG. 2  shows plug  10  without plug cover  11 , and plug lever  13  is shown in the starting position. A pressure plate  16  is placed into a receptacle region  18  of plug body  12 , pressure plate  16  having channels  20   a  for guiding electrical lines into plug body  12 . 
       FIG. 3  shows plug  10  without plug cover  11  and without plug lever  13 , in an exploded view. In receptacle region  18  of plug body  12 , a mat seal  22  can be placed between plug body  12  and pressure plate  16 . 
     Mat seal  22  has channels  20   b  for the sealed guidance of electrical lines. If pressure plate  16  and mat seal  22  are placed into receptacle region  18  of plug body  12 , then channels  20   a  of pressure plate  16  open into channels  20   b  of mat seal  22 , and channels  20   b  of mat seal  22  in turn open into channels  20   c  of plug body  12 , so that continuous channels  20   a ,  20   b ,  20   c  are formed. The electrical lines of a wiring harness can in this way be guided via receptacle opening  15  of plug cover  11  through continuous channels  20   a ,  20   b ,  20   c  into plug body  12  in order to produce an electrical connection with a plug module  25 . In this way, the course of channels  20   a ,  20   b ,  20   c  defines an axial direction of plug  12 . 
     Plug body  12 , pressure plate  16 , and mat seal  22  can each have channels having different diameters that can be used for the guidance or accommodation of electrical lines having different diameters, such as lines for power supply and/or lines for a transmission of signals. 
     Mat seal  22  has in addition an upper radial seal  26   a  for sealing plug  10  that laterally surrounds mat seal  22 , i.e. that surrounds mat seal  22  laterally in a plane orthogonal to the axial direction. Receptacle region  18  of plug body  12 , into which mat seal  22  and pressure plate  16  can be placed, has a boundary  24  that surrounds mat seal  22  and pressure plate  16  in annular fashion so that upper radial seal  26   a  is situated between boundary  24  of receptacle region  18  and a central region  37 , having channels  20   b , of mat seal  22 . 
       FIG. 4  shows plug  10  in a cross-section along a center plane that runs parallel to the axial direction, pressure plate  16  and mat seal  22  being placed into receptacle region  18  of plug body  12 , so that channels  20   a  of pressure plate  16 , channels  20   b  of mat seal  22  and channels  20   c  of plug body  12  open into one another, forming continuous channels  20   a ,  20   b ,  20   c  for guiding the electrical lines. Channels  20   b  of mat seal  22  also have a tapering region  31  that is fashioned to seal the electrical lines inside mat seal  22 . 
     Alternatively or in addition to tapering region  31 , channels  20   b  of mat seal  22  can have elastic elements (not shown), for example made of silicone, that can be situated inside the channels and that surround the electrical lines in sealing fashion in their routing through mat seal  22 . Pressure plate  16  and plug body  12  themselves can also have a tapering region and/or elastic elements inside channels  20   c ,  20   a  for the sealing guidance of the electrical lines. 
     To produce an electrical connection between the electrical lines accommodated in plug body  12  and electrical contacts  29  of a plug module  25 , plug  10  is placed onto plug module  25 , plug module  25  having a collar  27  that is accommodated by plug base  14 . Plug body  12  has in addition a plug element  33  that is fashioned so as to accommodate electrical contacts  29  of plug module  25 . 
     In addition, a circumferential sealing element  35  is situated around plug base  14 , the sealing element being realized so as to be accommodated between collar  27  of plug module  25  and plug base  14 , so that plug  10  plugged onto plug module  25  is sealed relative to a surrounding environment. 
     Pressure plate  16  and mat seal  22  are fashioned so as to cooperate in such a way that when they are placed into receptacle region  18  of plug body  12  through displacement of pressure plate  16  in the axial direction an edge region  28  of mat seal  22  is spread in the radial direction, so that upper radial seal  26   a  of mat seal  22  is pressed against boundary  24  of receptacle region  18 , and plug body  12  is sealed. 
     Edge region  28  of mat seal  22  is fashioned, at least in a partial area, as an inclined surface  39  inclining upward to boundary  24  of receptacle region  18 . So that edge region  28  of mat seal  22  can be spread by the displacement of pressure plate  16  in order to seal plug  10 , pressure plate  16  has an edge region  30  that is fashioned as a press-on surface cooperating with inclined surface  39  of edge region  28  of mat seal  22 , and has, at least in a partial area, an incline differing from inclined surface  39  of edge region  28  of mat seal  22 . 
     Underneath upper radial seal  26   a  of mat seal  22 , mat seal  22  has a lower radial seal  26   b  that also runs laterally around the circumference of mat seal  22 . Lower radial seal  26   b  is already pressed against boundary  24  of receptacle region  18  when mat seal  22  is placed into receptacle region  18 , so that mat seal  22  is held in a position in which channels  20   b  open into channels  20   c  of plug body  12 . In addition, plug  10  is sealed by lower radial seal  26   b  of mat seal  22 . 
       FIG. 5  shows a perspective detail view of mat seal  22  in which edge region  28 , fashioned so as to cooperate with pressure plate  16 , can be seen clearly. Here, edge region  28  is fashioned, in a partial area surrounding central region  37 , as inclined surface  39 , inclined surface  39  inclining up to boundary  24  of receptacle region  18  of plug body  12  and being fashioned so as to cooperate with edge region  30  of pressure plate  16 . Edge region  30  of pressure plate  16  here has, at least in a partial region, an incline differing from inclined surface  39  of edge region  28  of mat seal  22 , so that when pressure plate  16  is displaced in the axial direction a radial force component acts on edge region  28  of mat seal  22  and this edge region is spread radially, so that upper radial seal  26   a  is pressed against boundary  24  of plug body  12 . 
     Alternatively, edge region  28  of mat seal  22  can also for example be formed in steps or as a vertical spreadable surface running parallel to the axial direction. In such a specific embodiment, edge region  30  of pressure plate  16  is then correspondingly fashioned so that edge region  28  of mat seal  22  is spread by a displacement of pressure plate  16  in the axial direction to boundary  24  of receptacle region  18  of plug body  12 , and upper radial seal  26   a  can be pressed against boundary  24 . 
     In addition, inclined surface  39  of edge region  28  of mat seal  22  is surrounded by a horizontal surface  41  that forms the outermost edge of mat seal  22 . When pressure plate  16  is displaced in the axial direction, via horizontal surface  41  and via central region  37  an axial force component acts on mat seal  22 , so that the overall mat seal  22  is pressed in the axial direction against plug body  12 . 
       FIG. 6  shows a side view of mat seal  22  of  FIG. 5 , in which the two radial seals  26   a ,  26   b  can be seen clearly. Upper radial seal  26   a  protrudes somewhat less from edge region  28  of mat seal  22  then does lower radial seal  26   b . As a result, when mat seal  22  is placed into plug body  12 , but before pressure plate  16  is moved axially downward, upper radial seal  26   a  is not pressed, or is pressed only slightly, against boundary  24  of receptacle region  18 , and only lower radial seal  26   b  is pressed completely against boundary  24  of receptacle region  18 . 
     In addition, mat seal  22  is made asymmetrically with reference to a side  32  facing pressure plate  16  and a side  34  facing away from pressure plate  16 ; i.e., mat seal  22  is not symmetrical relative to a plane normal to the axial direction. Here, mat seal  22  has a circumference that is larger on side  32  facing pressure plate  16  than on side  34  facing away from pressure plate  16 . 
     In addition, mat seal  22  has, on side  34  facing away from pressure plate  16 , a sealing body  36  that is fashioned as a sealing element running around the axial direction. As described above, when pressure plate  16  is displaced in the axial direction, an axial force is introduced into mat seal  22  via horizontal surface  41  of edge region  28  of mat seal  22  and via central region  37  of mat seal  22 , so that the entire mat seal  22 , and in particular sealing body  36 , is pressed against plug body  12 , axially sealing plug  10 . 
     Sealing body  36 , as well as radial seals  26   a ,  26   b , can be made of silicone and can be connected fixedly, i.e. in particular in one piece, to mat seal  22 . Alternatively, radial seals  26   a ,  26   b  can be fashioned for example in the form of O-rings that can be placed around mat seal  22 , for example in recesses that run laterally in the circumference of mat seal  22 . In addition, it is also possible for only one of radial seals  26   a ,  26   b  to be connected fixedly to mat seal  22 , and for the other radial seal to be fashioned as an O-ring. 
     In addition, it is to be noted that “having” does not exclude any other elements, and “one” or “a” does not exclude a plurality. In addition, it is to be noted that features described with reference to one of the above exemplary embodiments can also be used in combination with other features of other exemplary embodiments described above.