Abstract:
The invention relates to a plug connector ( 10 ) for the detachable connection of a number of cable pairs ( 97, 98 ) with a conductor cross-section of more than 10 mm 2 , in particular, for the supply of the welding current in welding robots, wherein individual contact elements ( 52, 60 ), with a conducting connection to the cables ( 97, 98 ), may be plugged into an insulated plug housing ( 11 ) with a clipping action and are detachably held in the plug housing ( 11 ) or terminal housing ( 12 ), the clipping action of the contact elements ( 52, 60 ) in the housings ( 11, 12 ) being achieved by an elastic deformation of the housings ( 11, 12 ). Manipulation is facilitated in that the housing ( 11, 12 ) is made from a material of such a hardness that the plugging in and exchange of contact elements can be achieved without the use of tools.

Description:
TECHNICAL FIELD 
   The present invention relates to the field of electrical plug-type connections. It relates to a plug-type connection in accordance with the preamble of claim  1 . 
   PRIOR ART 
   In robot technology, in particular in industrial welding robots, comparatively high currents in the region of 100 A or more need to be guided from the base of the robots along the robot arm to the apparatuses fitted at the end of the robot arm (welding tools etc.). For this purpose, wiring with the corresponding conductor cross sections (typically 10-50 mm 2 ) are used which are guided along the robot arm and are equipped with corresponding plug-type connections at the joints (in particular at the base and at the end of the arm). 
   For the application with welding robots, the applicant already markets plug-type connections from the TSB/TSS series (primary circuit plug-type connectors for welding transformers), in which individual contacts in the form of sockets and corresponding pins are electrically connected to the cable ends, from which the insulation has been stripped, by means of a screw-type or crimping connection and are then introduced into corresponding (cylindrical) insulating housings (see in this regard the catalog MC Roboticline 07.2001 (ex Ho7b), 2001; pages 18, 19 and 31). In accordance with the assembly instructions MA 200, special tools are required for this purpose in order to press the individual contacts, which are resting on the cable ends, into the bores provided for this purpose in the insulating housings and to press them out again, if necessary, in the event of repair work (pages 41-44 of the abovementioned catalog). 
   The known plug-type connections for the primary circuit of welding transformers in the welding robots sector have proven to be successful in practice. However, special tools (pin introduction tool, pin removal tool, socket introduction tool, socket removal tool etc.) are required for introducing and removing the individual contacts, and these tools not only need to be kept at the assembly/dismantling location, but also require special handling of the insulating housings when they are used. Since, in the case of welding robots, the associated cables are subject to pulse-like mechanical loads owing to the pulse-like welding currents and the associated magnetic fields, the cables need to be replaced more often during continuous operation of the robots in an industrial environment. In this case it is desirable for such a replacement to be capable of being carried out simply and quickly and also under restricted space conditions. 
   Furthermore, in the case of new robot types it is now practice to lay the supply and control cables or cable harnesses, which until now have been guided on the outside along the robot arms, in the interior of the arms in order to prevent possible collisions between the cable harnesses and objects arranged in the vicinity of the swiveling range of the robot and therefore also to simplify programming. By laying the cables in the interior of the robot arm, simplified assembly/dismantling of the plug-type connections becomes even more important under restricted conditions as well. 
   Furthermore, the plug-type connections should be as tight against one another as possible in a simple manner, both in the region of contact-making in the plugged-in state and in the region of the cable entry point (protection rating IP67). 
   Furthermore it is desirable to be able to secure the plug-type connection in the plugged-in state against unintentionally becoming unplugged in a simple manner and to be able to fix the plug-type connection at the use location in a simple manner. 
   DESCRIPTION OF THE INVENTION 
   The object of the invention is to specify a plug-type connection for the described use which avoids the disadvantages of previous plug-type connections and can be assembled and dismantled simply and quickly without special aids and also under restricted spatial conditions. 
   The object is achieved by the entirety of the features of claim  1 . The essence of the invention consists in, in the case of the plug-type connection according to the invention, individual contact elements, which are conductively connected to the cables, being plugged into an insulating plug housing and/or an insulating socket housing so as to latch in and being held replaceably in the plug housing and socket housing, respectively, wherein the latching-in of the contact elements in the housings is achieved by elastic deformation of the housings, and wherein the housings are made from a material with a hardness which makes it possible for the contact elements to be plugged in and replaced without the aid of tools. The material of the housings is therefore “soft” enough for the individual contacts, which are located at the cable ends and are equipped with latching apparatuses, to be capable of being pressed into the bores provided for this purpose in the housings and possibly also withdrawn again without the use of special tools, i.e. only by hand, counter to a certain resistance. The “softness” of the material in this case depends on the design of the latching mechanism which also determines the level of elastic deformation required. 
   In accordance with a configuration of the invention, the plug housing and/or the socket housing are designed to be integral and are made from a thermoplastic elastomer (TPE). 
   A further configuration of the invention is characterized by the fact that the contact elements are arranged in the plug housing and/or the socket housing parallel next to one another in one plane, and in that in each case three contact elements are arranged next to one another in the housings. 
   With respect to the mechanical stability and sealtightness, it is particularly advantageous if cable sleeves for accommodating the ends of the cables connected to the contact elements are arranged on the plug housing and/or socket housing, and if releasable fastening means are provided, by means of which the cables can be fixed in the cable sleeves. 
   Preferably, the fastening means each comprise a cable strain-relief clamp, which fixedly clamps the cables in the cable sleeves as a result of external pressure on the cable sleeves, wherein the cable strain-relief clamps each comprise an upper part and a lower part, which surround the cable sleeves on opposite sides and can be connected to one another, and wherein the cable sleeves are in the form of hollow cylinders which are arranged next to one another parallel at a distance, and the upper part and the lower part of the cable strain-relief clamps are each in the form of a bar, which extends transversely over the cable sleeves and is equipped, on the side facing the cable sleeves, with cutouts so as to conform to the cable sleeves. 
   In particular, the upper and lower parts of the cable strain-relief clamps have mutually aligned bores in order for them to be connected to one another, wherein the upper and lower parts of the cable strain-relief clamps are connected to one another by means of fastening screws, which extend through the bores, and exert external pressure on the cable sleeves. 
   Another configuration is characterized by the fact that the cable strain-relief clamps and therefore the entire plug-type connection is fixedly screwed by means of the fastening screws on a base. 
   A further configuration of the invention is characterized by the fact that the plug housing and the socket housing can be secured against the plug-type connection being pulled apart from one another by means of a securing clip, which, in the plugged-together state of the plug-type connection, can be inserted into the housings, wherein the securing clip preferably comprises an elongate base plate, from which pins protrude in perpendicular fashion in one direction at the ends, and through-bores, into which the securing clip with the pins can be plugged, are provided in the housings. 
   It is particularly favorable for the application if the pins are provided with slots at the free ends and have latching heads, with which they latch in at the outlet of the through-bores, and if recessed grips are integrally formed on the securing clip, by means of which recessed grips the securing clip can be drawn out of the housings without the use of a tool. In particular, the securing clip is designed to be integral and is produced as an injection molded part from a plastic. 
   The cable strain-relief clamps are preferably produced from a plastic, in particular a fiber-reinforced polyamide. 
   In order to achieve sealing and clamping which is improved further still, it is advantageous if the cable sleeves taper slightly conically inwards towards the outlet, and if the cutouts are likewise slightly conical. 
   In accordance with a further configuration of the invention, slightly conical socket receptacle sections, which are positioned next to one another at a distance and parallel and receive the contact sockets of the female contact elements, are arranged on the socket housing; corresponding contact protection means are arranged on the plug housing which receives the socket receptacle sections if the plug-type connection has been plugged together. Preferably in this case sealing beads are formed on the outside on the socket receptacle sections in order to increase the sealtightness. 
   Another configuration is characterized by the fact that the housings each have connection chambers for receiving the contact elements, that in each case one latching tab with a latching groove, which is positioned behind the latter in the plug-in direction, is formed in the connection chambers, and that in each case one holding groove and a latching collar is provided on the contact elements so as to interact with the latching tab and the latching groove. In order to facilitate the insertion process, in this case the latching collar has a sloping flank on the plug-in side. 
   In order to further improve handling, recessed grips for drawing the housings apart from one another can be formed on the housings. 
   In order to make it possible to use the plug-type connection in cables with different outer diameters, it is advantageous if the cable sleeves are split into two sections, which are arranged one behind the other in the plug-in direction, wherein the inner diameter of the section which is positioned further towards the outside is greater than the inner diameter of the other section. 
   In accordance with another configuration, the upper part and the lower part of the cable strain-relief clamps are guided with respect to one another by means of guide pins, wherein, preferably, the guide pins are coded for the purpose of clear orientation of the parts with respect to one another. 
   Furthermore, it is advantageous if mutually fitting coding elements are provided on the strain-relief clamp and on the associated plug or socket housing and ensure a clear orientation of the strain-relief clamp with respect to the associated plug or socket housing. 

   
     BRIEF EXPLANATION OF THE FIGURES 
     The invention will be explained in more detail below with reference to exemplary embodiments in connection with the drawing, in which: 
       FIG. 1  shows a perspective illustration of a plugged-together plug-type connection (without cables) in accordance with a preferred exemplary embodiment of the invention; 
       FIG. 2  shows the plug-type connection from  FIG. 1  in a plan view from above; 
       FIG. 3  shows a perspective illustration of the socket housing of the plug-type connection from  FIG. 1 ; 
       FIG. 4  shows a perspective illustration of the longitudinal section through the socket housing from  FIG. 3 ; 
       FIG. 5  shows a perspective illustration of the plug housing of the plug-type connection from  FIG. 1 ; 
       FIG. 6  shows a perspective illustration of the longitudinal section through the plug housing from  FIG. 5 ; 
       FIG. 7  shows the longitudinal section through a female contact element, which can be inserted removably into the socket housing from  FIG. 3 ; 
       FIG. 8  shows the longitudinal section through a male contact element, which can be inserted removably into the plug housing from  FIG. 5 ; 
       FIG. 9  shows a perspective illustration, viewed from above, of the securing clip from  FIG. 1  for securing the plugged-together plug-type connection from  FIG. 1 ; 
       FIG. 10  shows the securing clip from  FIG. 9  in a perspective illustration, viewed from below; 
       FIG. 11  shows, in two subfigures (a) and (b), the side view of the securing clip from  FIG. 9  and the section in a sectional plane passing through two pins; 
       FIG. 12  shows, in two subfigures (a) and (b), a perspective front and rear view of the upper part of the cable strain-relief clamp from  FIG. 1 ; 
       FIG. 13  shows, in two subfigures (a) and (b), a perspective front and rear view of the lower part of the cable strain-relief clamp from  FIG. 1 ; 
       FIG. 14  shows the upper and lower part of a strain-relief clamp similar to  FIGS. 12 and 13  with coded guide pins and coding elements for interaction with the plug housing from  FIG. 15 ; 
       FIG. 15  shows a perspective illustration of a plug housing similar to that in  FIG. 5  with additional coding elements for interaction with the strain-relief clamp from  FIG. 14 ; and 
       FIG. 16  shows a longitudinal section through a completely assembled and plugged-together plug-type connection in accordance with a preferred exemplary embodiment of the invention. 
   

   APPROACHES FOR IMPLEMENTING THE INVENTION 
     FIG. 1  reproduces a perspective illustration of a plugged-together plug-type connection (without the cables connected to the contact elements) in accordance with a preferred exemplary embodiment of the invention. In the example, the plug-type connection  10  is designed for connecting three cable pairs, with the connection of two cable pairs or more than three cable pairs likewise being conceivable. In the example, the plug-type connection  10  comprises an insulating plug housing  11  (illustrated individually in  FIGS. 5 and 6 ), an insulating socket housing  12  (illustrated individually in  FIGS. 3 and 4 ), two cable strain-relief clamps  13  and  14 , and a securing clip  15 , which secures the plugged-together housings  11 ,  12  against unintentionally becoming unplugged. All of parts  11 , . . . ,  15  of the plug-type connection  10  are made from a plastic. The housings  11 ,  12  are preferably produced from a thermoplastic elastomer (TPE), whose hardness is set such that the contact elements shown in  FIGS. 7 and 8  can be pressed into the housings  11 ,  12 , but also withdrawn again (on the cables) without special aids (tools).  FIG. 2  shows the plugged-together plug-type connection  10  in a plan view from above. 
   The cable strain-relief clamps  13 ,  14  each comprise an upper part ( FIG. 12 ) and a lower part ( FIG. 13 ), which can be connected to one another by means of fastening screws  18 ,  19  in order to exert the necessary external pressure on the parts of the housing lying therebetween (cable sleeves  27  and  45 , respectively). The cable strain-relief clamps  13 ,  14  are preferably produced from a fiber-reinforced polyamide in order to achieve the required mechanical strength. 
   The socket housing  12  illustrated in  FIGS. 3 and 4  is designed to be integral. It comprises a central part  20 , which extends transversely with respect to the plug-in direction and through which two vertical through-bores  24  and  25  run next to one another, into which bores the securing clip  15  can be plugged with two of its four pins ( 69 ,  70 ,  75 ,  76  in  FIG. 10 ). Three socket chambers  21 , . . . ,  23 , which extend parallel to one another in the plug-in direction and lie in one plane, are integrally formed on the central part  20 , wherein in each case one connection chamber  32 , which ends at the front in a socket receptacle section  30  and at the rear in a cable sleeve  27 , runs through said socket chambers  21 , . . . ,  23 . Recessed grips  28  are integrally formed at the lateral ends of the central part  20 , on which recessed grips  28  the hand can be placed when unplugging the plug-type connection  10 . The arrangement of the individual plug-type connections in one plane means a particularly flat design of the plug-type connection, which is advantageous when integrating the associated cables in the robots. 
   The individually shaped cable sleeves  27 , which are spaced apart from one other, are designed to be cylindrical on the outside. On the inside, they are split into two sections  33 ,  34 , which are arranged behind one another in the plug-in direction, wherein the outer section  34  has a greater inner diameter than the section  33  lying further inwards. The two sections  33 ,  34  with the different inner diameters make it possible to receive cables with different outer diameters (different sheath designs) given the same conductor cross section. It is thus conceivable, for example, to connect cables with a conductor cross section of 35 mm 2  which have an outer diameter of between 11 and 17 mm. The same metal parts (contact elements  52 ,  60  from  FIGS. 7 and 8 ) are used for all of these cables. In the sections  33 ,  34 , the cable sleeves  27  are each tapered slightly conically towards the outside in terms of their inner diameter and have concentric ribbing on the inner wall, which ribbing assists both the mechanical fixing and the sealing of the cable in the cable sleeve  27 . In each case one peripheral bead  26  is integrally formed at the outer ends of the cable sleeves  27 , which peripheral bead  26  ensures the fit of the cable strain-relief clamp  14  on the cable sleeves  27 . 
   The individually shaped socket receptacle sections  30 , which are spaced apart from one another, taper slightly conically towards the front on the outside. When the plug-type connection  10  is plugged together, they are plugged into corresponding contact protection means  67  in the plug housing  11  ( FIG. 5 ). The socket receptacle sections  30  receive the contact sockets ( 53 ) of the female contact elements  52  ( FIG. 7 ). Two sealing beads  29 ,  31 , which are used for sealing the plug-type connection between the two housings  11  and  12 , are formed on the socket receptacle sections  30  in such a way that they are spaced apart axially on the outside. 
   The connection chambers  32  in the socket housing  12  are provided for receiving the female contact elements  52  shown in  FIG. 7 . For this purpose, in each case one inwardly projecting latching tab  35  with a latching groove  36 , which lies behind said latching tab  35  in the plug-in direction, is formed in the connection chambers  32 , which latching tabs interact with a matching holding groove  58  and a matching latching collar  57  on the contact element  52 . In order to make it easier to plug the contact element  52  into the connection chamber  32  of the socket housing  12 , the latching collar  57  of the contact element  52  has a sloping flank on the plug-in side. In order to make it easier for the contact element  52  to be withdrawn from the connection chamber  32 , the side walls of the holding groove  58  can be designed to be slightly sloping. 
   If the contact element  52  with the contact socket  53  leading is introduced into the connection chamber  32  from the rear through the cable sleeve  27 , it can initially be pushed in, without any considerable resistance, until it hits the rear rim of the latching tab  35  with the latching collar  57 . When it is pushed in further assisted by the sloping flank on the latching collar  57 , the latching tab  35  is pressed elastically radially outwards until it snaps back completely into the holding groove  58  behind the latching collar  57  if, at the same time, the latching collar  57  latches into the latching groove  36 . The contact socket  53  of the contact element  52  is then resting in the socket area  37  provided for this purpose of the socket housing  12  and is covered at the front by a contact protection means  47  so as to prevent unintentional contact being made. If the contact element  52  has reached this end position, the cable reaches with its sheath into the cable sleeve  27  and can be fixed there by means of the cable strain-relief clamp  14  (cables  97 ,  98  in  FIG. 16 ). 
   Similar conditions prevail in the case of the plug housing  11  shown in  FIGS. 5 and 6 . The plug housing  11  is designed to be integral. It comprises three plug chambers  39 , . . . ,  41 , which extend parallel to one another in the plug-in direction and lie in one plane and through which in each case one connection chamber  48  runs, which ends at the front in a common plug receptacle section  38  and at the rear in each case in a cable sleeve  45 . Likewise recessed grips  46  are integrally formed at the lateral ends of the plug housing  11 , with it being possible for the hand to be placed on said recessed grips  46  when the plug-type connection  10  is unplugged. 
   The individually shaped cable sleeves  45 , which are spaced apart from one another, are designed to be cylindrical on the outside on the socket housing  12  in the same way as the cable sleeves  27  and on the inside are split into two sections  33 ,  34 , which are arranged behind one another in the plug-in direction, with concentric ribbing. Likewise, a peripheral bead  44 , which secures the fit of the cable strain-relief clamp  13  on the cable sleeve  45 , is integrally formed on the outer ends of the cable sleeves  45 . 
   The connection chambers  48  in the plug housing  11  are provided for receiving the male contact elements  60  shown in  FIG. 8 . For this purpose, in each case one inwardly projecting latching tab  49  with a latching groove  50  lying behind it in the plug-in direction is formed in the connection chambers  48 , which latching tabs interact with a matching holding groove  65  and a matching latching collar  64  on the contact element  60 . In order to make it easier to plug the contact element  60  into the connection chamber  48  of the plug housing  11 , the latching collar  64  of the contact element  60  also has a sloping flank on the plug-in side. In order to make it easier to withdraw the contact element  60  from the connection chamber  48 , the side walls of the holding groove  65  can also be designed to be slightly sloping here. 
   If the contact element  60  with the pin  63  leading is inserted into the connection chamber  48  from the rear through the cable sleeve  45 , initially it can be pushed in, without any considerable resistance, until it hits the rear rim of the latching tab  49  with the latching collar  64 . When it is pushed in further assisted by the sloping flank on the latching collar  64 , the latching tab  49  is pressed elastically radially outwards until it snaps back completely into the holding groove  65  behind the latching collar  64  if, at the same time, the latching collar  64  latches into the latching groove  50 . The pin  63  of the contact element  60  then protrudes into the plug area  51  of the plug housing  11  provided for this purpose and is surrounded by the socket receptacle section  30  of the socket housing  12  if the plug-type connection  10  has been plugged together. If the contact element  60  has reached this end position, the cable reaches with its sheath in the cable sleeve  45  and can be fixed there by means of the cable strain-relief clamp  13 . The slightly conical embodiment of the plug area  51  and the socket receptacle section  30  and the sealing beads  29 ,  31  ensures that, in the plugged-in state, a sealtightness in accordance with IP67 is achieved at this point (see  FIG. 16 ). 
   The preferred female contact element  52  shown in  FIG. 7  comprises, in a manner known per se, a contact socket  53  with a blind bore  55  and a shoulder  59 , onto which a press bush  54  is pushed and fixedly soldered. The cable end with the exposed conductor is pushed into the press bush  54  and compressed. An annular groove  56  for receiving a multi-contact contact lamination, which is bent in annular fashion, is provided in the blind bore  55 , wherein the multi-contact contact lamination makes the electrical contact with the inserted pin  63  of the male contact element  60  from  FIG. 8 . The male contact element  60  preferably comprises a contact plug  61  with a shoulder  66  arranged at the rear, onto which a press bush  62  is pushed and fixedly soldered. The cable is in this case fitted in the same way as in the case of the contact element  52  in  FIG. 7 . 
   As has already been mentioned further above, the cable strain-relief clamps  13 ,  14  each comprise an upper part  16  ( FIG. 12 ) and a lower part  17  ( FIG. 13 ), which surround the cable sleeves  27  and  45 , respectively, on opposite sides and can be connected to one another. The upper part  16  and the lower part  17  of the cable strain-relief clamps  13 ,  14  are each in the form of a bar, which extends transversely over the cable sleeves  27 ,  45  and is equipped, on the side facing the cable sleeves  27 ,  45 , with approximately semicylindrical cutouts  77 , . . . ,  79  and  84 , . . . ,  86 , respectively, so as to conform to the cable sleeves  27 ,  45 . The cutouts  77 , . . . ,  79  and  84 , . . . ,  86 , respectively, are preferably designed to be slightly conical in order to achieve improved clamping and sealtightness in accordance with IP67 in interaction with the slightly conical sections  33 ,  34  in the cable sleeves  27 ,  45 . 
   The upper and lower parts  16 ,  17  of the cable strain-relief clamps  13 ,  14  have mutually aligned bores  82 ,  83  and  89 ,  90 , respectively, so as to connect them to one another. Fastening screws  18 ,  19  are plugged through these bores  82 ,  83  and  89 ,  90 , respectively, in order to connect the two parts  16 ,  17  to one another and to exert external pressure on the cable sleeves  27 ,  45 . For this purpose, corresponding nuts can be arranged on the opposite side. However, it is also possible to fixedly screw the cable strain-relief clamps  13 ,  14  and therefore the entire plug-type connection  10  on a base (mounting plate or the like) by means of the fastening screws  18 ,  19 . In addition, in order to align the clamp parts, guide pins  80 ,  81  can be provided on the upper part  16  and/or lower part  17 , which guide pins  80 ,  81  enter, in guiding fashion, corresponding bores  87 ,  88  on the lower part  17  and/or upper part  16 . 
   It is furthermore possible to secure the plug housing  11  and the socket housing  12  by means of a securing clip  15  which can be plugged in so as to prevent the plug-type connection  10  from being drawn apart. The securing clip suitable for this purpose ( FIGS. 9-11 ) comprises an elongate base plate  68 , from which pins  69 ,  70  and  75 ,  76  protrude perpendicularly at the ends in one direction in pairs. Corresponding vertical through-bores  24 ,  25  and  42 ,  43 , respectively, are provided in the housings  11 ,  12 , into which through-bores the securing clip  15  can be plugged with the pins  69 ,  70  and  75 ,  76 , respectively. 
   The pins  69 ,  70 ,  75 ,  76  are provided with slots at their free ends and have latching heads, with which they latch in at the outlet of the through-bores  24 ,  25  and  42 ,  43 , respectively. Advantageously, recessed grips  73 ,  74  are integrally formed laterally on the securing clip  15 , by means of which recessed grips  73 ,  74  the securing clip  15  can be withdrawn from the housings  11 ,  12  without the use of a tool. The securing clip  15  is preferably designed to be integral and is produced as an injection-molded part from a plastic. 
   In order to ensure clear assignment of the two parts of the strain-relief clamps with respect to one another and furthermore to make it possible to clearly orientate the strain-relief clamps relative to the plug housing or socket housing, coding means can be arranged on the parts. Examples of such coding means are illustrated in  FIGS. 14 and 15 . The cable strain-relief clamp from  FIG. 14  has, similarly to  FIGS. 12 and 13 , an upper part  16 ′ and a lower part  17 ′, which together form the clamp. Two hexagonal openings  95 ,  96  can be seen on the upper side of the lower part  17 ′, which hexagonal openings  95 ,  96  receive corresponding nuts if the two parts are screwed to one another. The two parts  16 ′,  17 ′ are guided with respect to one another by guide pins  80 ′,  81 ′, which in this example are coded: the guide pin  80 ′ on the upper part  16 ′ has a rectangular cross section, which corresponds to that of a bore in the lower part  17 ′ with a rectangular cross section. The guide pin  81 ′ on the upper part  16 ′, in contrast, has a circular cross section, which corresponds to that of a bore in the lower part  17 ′ with a circular cross section. Other codings are also conceivable. 
   Furthermore, laterally protruding, tab-shaped coding elements  91 ,  92  are integrally formed on the lower part  17 ′ of the strain-relief clamp, which coding elements  91 ,  92  enter corresponding recesses (coding elements  93 ,  94 ) in the plug housing  11 ′ in  FIG. 15  if the strain-relief clamp is fastened on the plug housing  11 ′ in the correct orientation. This ensures that the strain-relief clamps clamp the cables ending in the plug-type connection in the desired manner. Furthermore, it can be seen on the plug housing  11 ′ in  FIG. 15  that the contact protection means  67  can have different opening diameters, which make it possible for there to be clear assignment between the two plug-type connectors during the insertion process. 
   Overall, the functional principle of the plug-type connection according to the invention can be summarized as follows: 
   The plug-type connection is designed, for example, for a cable cross section of 35 mm 2 . The cables may be three fixed cable types, whose outer diameter may vary from approximately 11 mm to approximately 17 mm. The cables are pressed against one and the same metal part (contact element). Then the cables together with the metal part (contact element) are plugged into the insulating housing from the rear through the cable sleeve without the use of a tool until they noticeably latch into it. 
   If all of the three contacts have been latched in, the cable strain-relief clamp can be plugged onto the cable sleeves. Now the cable strain-relief clamp can be screwed against a mounting plate with the corresponding threads by means of two (M5) screws. With this strain relief, the required holding force of the cables in the insulation is achieved. Furthermore, the protection rating IP67 on the cable sleeve is achieved thereby. 
   Furthermore, the entire plug-type connection is held and locked on the mounting plate via the screws in the cable strain relief. 
   For dismantling the device, the complete sequence is conducted in reverse order. 
   LIST OF REFERENCE SYMBOLS 
   
       
         10  Plug-type connection 
         11 ,  11 ′ Plug housing 
         12  Socket housing 
         13 ,  14  Cable strain-relief clamp 
         15  Securing clip 
         16 ,  16 ′ Upper part (cable strain-relief clamp) 
         17 ,  17 ′ Lower part (cable strain-relief clamp) 
         18 ,  19  Fastening screw 
         20  Central part (socket housing) 
         21 , . . . ,  23  Socket chamber (socket housing) 
         24 ,  25  Through-bore (for securing clip) 
         26 ,  44  Peripheral bead 
         27 ,  45  Cable sleeve 
         28 ,  46  Recessed grip 
         29 ,  31  Sealing bead 
         30  Socket receptacle section 
         32 ,  48  Connection chamber 
         33 ,  34  Section (cable receptacle) 
         35 ,  49  Latching tab 
         36 ,  50  Latching groove 
         37  Socket area 
         38  Plug receptacle section 
         39 , . . . ,  41  Plug chamber (plug housing) 
         42 ,  43  Through-bore (for securing clip) 
         47 ,  67  Contact protection means 
         51  Plug area 
         52  Contact element (female) 
         53  Contact socket 
         54 ,  62  Press bush 
         55  Blind bore 
         56  Groove (contact lamination) 
         57 ,  64  Latching collar 
         58 ,  65  Holding groove 
         59 ,  66  Shoulder 
         60  Contact element (male) 
         61  Contact plug 
         63  Pin 
         68  Base plate 
         69 ,  70  Pin 
         71  Slot 
         72  Latching head 
         73 ,  74  Recessed grip 
         75 ,  76  Pin 
         77 , . . . ,  79  Cutout 
         80 ,  81  Guide pin 
         80 ′,  81 ′ Guide pin (coded) 
         82 ,  83  Bore 
         84 , . . . ,  86  Cutout 
         87 ,  88  Bore 
         89 ,  90  Bore 
         91 ,  92  Coding element (strain-relief clamp) 
         93 ,  94  Coding element (plug housing) 
         95 ,  96  Hexagonal opening 
         97 ,  98  Cable