Abstract:
An electrical plug-in connector is in the form of a cable plug connector or a device connector plug. A particularly reliable and tightly-sealed connector may be achieved, whereby the plug-in connector is disclosed, and contains a connector mechanism, which is self-closing on bringing the parts for connection together. The plug-in connector further contains a radial seal for sealing the parts connected together.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This is a continuing application, under 35 U.S.C. § 120, of copending international application No. PCT/EP2003/010763, filed Sep. 27, 2003, which designated the United States; this application also claims the priority, under 35 U.S.C. § 119, of German patent application No. 102 46 450.2, filed Oct. 4, 2002; the prior applications are herewith incorporated by reference in their entirety.  
       BACKGROUND OF THE INVENTION  
     FIELD OF THE INVENTION  
       [0002]     The invention relates to an electrical plug-in connector, in particular in the form of a cable plug-in connector or a device connection plug.  
         [0003]     In order to achieve a particularly good seal, it is known to insert sealing rings in the contact-protection sleeves surrounding the pin contacts of a plug-in connector. The sealing rings act as axial seals, i.e. are compressed when the socket and plug parts are connected. In this case, sealing forces are introduced into the plug-in connection. In order to ensure a permanent seal, for this reason, materials, which have a particularly high strength are always required for producing the plug-in connector or additional securing elements are always required for securing the plug-in connection.  
       SUMMARY OF THE INVENTION  
       [0004]     It is accordingly an object of the invention to provide an electrical plug-in connector that overcomes the above-mentioned disadvantages of the prior art devices of this general type, which closes in a particularly reliable and sealing manner.  
         [0005]     With the foregoing and other objects in view there is provided, in accordance with the invention, an electrical plug-in connector. The connector contains parts to be connected to each other for forming a plug/socket connection having plug-in connectors. A connection mechanism closes automatically when the parts are joined together. A contact-protection sleeve is provided and a radial seal is disposed on the contact-protection sleeve, for sealing the parts connected to one another, in a region of overlap between the plug-in connectors connected to one another.  
         [0006]     According to the invention, the plug-in connector has a connection mechanism, which closes automatically when the parts to be connected are joined together. Furthermore, the plug-in connector has a radial seal for the purpose of sealing the parts, which are connected to one another. The connection mechanism is configured to connect the plug-in connector to a further plug-in connector such that the radial seal is disposed in the region of overlap when the plug and the socket part are plugged together. When the socket part and the plug part are connected, the contact-protection sleeves, which are fitted on the socket part and which surround the plug sockets, can be pushed into corresponding contact-protection sleeves which surround the pin contacts on the plug part with a spacing. The radial seal is advantageously disposed in the region of the contact-protection sleeve, preferably on the contact-protection sleeve of the plug part.  
         [0007]     One basic principle of the invention relates to replacing the axial seal, which has been used to date with a radial seal. The sealing forces thus act radially, i.e. in the direction of the circumference of the plug-in connector and no longer in the axial connection direction of the plug-in connector. The radial seal therefore acts without sealing forces needing to be introduced into the plug-in connection. In other words, the sealing forces need no longer be applied through the plug-in connection or through additional securing apparatuses. This solution makes it possible to simplify the configuration of the plug-in connector. In particular, it may be manufactured completely from plastic without additional securing apparatuses being required, since only the grip of the plug-in connection, but no longer the sealing forces, need to be protected. The plug-in connectors obtained in this manner with force-free locking or latching are not only simple in design terms, but also have a particularly good seal, with the result that, for example, the requirements in accordance with IP 67 are fulfilled. A simple configuration of the plug-in connector is likewise achieved owing to the positive locking. In a very favorable case, only two parts are required for the connection, which can be plugged onto one another without using a tool. In this case, the plug-in connector according to the invention may be, for example, a cable plug-in connector or a device connection plug.  
         [0008]     In order to produce the plug-in connection, in this case a locking tongue is preferably used which connects the plug and the socket part to one another. Such a locking tongue is known, for example, from the German patent DE 34 40 043 C2, in particular from patent claims  1  to  4  therein. Since the locking is force-free owing to the use of a radial seal, it is sufficient to attach a single locking tongue. Despite the asymmetrical locking, a secure and tight connection is possible since there are no longer any counter-forces acting on the locking.  
         [0009]     In order to mount the device connection plug on a device wall, for example a luminaire housing, the plug has a mounting element, for example, in the form of a stop collar. An axial seal is fitted to the mounting element, by which seal the stop element bears against the housing wall surrounding the mounting opening. Furthermore, the plug-in connector bears a thread for the purpose of securing the stop collar on the housing wall by a screw connection.  
         [0010]     In one development of the invention, a two-part device connection plug is proposed which requires a much smaller housing bushing. Accordingly, the electrical plug-in connector contains an adapter element and a contact carrier, which can be connected to the adapter element. For this purpose, a specially configured adapter element having a bushing connection piece is used, with the result that the device connection plug can be used even in the case of housing bushings which have been narrowed to the dimensions of the cable diameter plus the housing wall thickness. The adapter element can be combined with the plug or socket contact carriers of the plug-in connector. One particular advantage is the fact that it is not necessary for the user to change existing housing holes. Second, in each case only one new adapter connection piece needs to be developed and produced, since it can be combined with already existing modules.  
         [0011]     If the plug-in connector is in the form of a cable plug-in connector, it has an automatically closing connection mechanism for the purpose of connecting the contact carrier of the plug-in connector to a strain-relief device and a radial seal for the purpose of sealing the parts, which are connected to one another. In another embodiment, the strain-relief device can simply be pushed onto the contact carrier. This considerably simplifies assembly. In this case, the strain-relief device is preferably pushed onto the contact carrier axially, i.e. in the longitudinal direction of the plug. The preferably sleeve-like strain-relief device is in this case, in accordance with a further embodiment of the invention, fixed to the contact carrier by a latching connection. The largely preassembled nature in which, for example, the strain-relief device and the contact carrier have already been connected to one another, makes the plug-in connector easy to use and easy to install.  
         [0012]     The radial seal, which is provided for purpose of sealing the connection, is disposed in the region of overlap between the strain-relief device and the contact carrier. The strain-relief device, which has been pushed onto the contact carrier, is preferably fixed with the aid of a union nut, which is fitted at one end. The union nut at the same time serves the purpose of providing a further seal with respect to the cable emerging from the plug-in connector.  
         [0013]     Even the embodiment as a cable plug-in connector may have, at one end, the above-described connection mechanism for the purpose of connecting a complementary plug part. The contact carriers of cable plug-in connectors and device connection plugs preferably have an identical configuration in this regard.  
         [0014]     The contact carrier has a contact region, which is disposed opposite the plug or socket face, for the purpose of connecting the conductors. The connection region preferably contains so-called push-in contacts, into which the conductors can be inserted in a simple manner. The wiring complexity is thus very low. The push-in contacts are in this case, in particular, in the form of spring-force terminals. However, screw, crimping, soldered or insulation displacement connections may also be used, for example. It is particularly advantageous if spring-force terminals are equipped with a double connection for two conductor ends per pole. In this case, the strain-relief device is preferably configured such that it ensures the connection of two round cables parallel to one another in one plug-in connector.  
         [0015]     It is particularly advantageous if the connection mechanism can be opened only using an actuating tool. This fulfills the requirements for re-connectable service plug-in connectors in accordance with EN 61535. With the particular configuration of the radial seal, in particular when release takes place by use of a tool, there is initially a form of pre-release of the plug-in connection. As a result, the frictional forces, which are then still to be overcome, of the radial seal between the connection parts, are no longer so large. It is thus possible for the connection to be released particularly easily.  
         [0016]     In a further advantageous embodiment of the invention, the plug-in connector contains a corresponding opener for the purpose of unlocking the connection mechanism. It is thus possible to use a plug-in connector, which can only be opened using a tool even in cases where plug-in connectors, which need to be opened by hand are usually used, without this resulting in additional complexity for the user. In this case, the opener is connected to the plug-in connector such that it can be released, preferably so as to form a latching or a snap connection. Furthermore, suitable encoding measures can be used to ensure that the opener can only be mounted on those plug-in connectors for which the use of the opener is desired.  
         [0017]     A particularly simple but nevertheless reliable actuation of the connection mechanism is possible by an opener. The opener has a release element for the purpose of unlocking the connection mechanism, which is fitted to an actuating element, which can preferably be deflected by hand. Such an opener can be of integral construction and can be made completely from plastic, as a result of which it can be produced in a particularly cost-effective manner.  
         [0018]     In one further preferred embodiment of the invention, the contact-protection sleeves surrounding the plug-in contacts are configured such that, in addition to protection against rotation by the use of corresponding encoding elements, protection against plugging is also achieved as regards plugging together pairs of plugs, which are not associated with one another.  
         [0019]     Other features which are considered as characteristic for the invention are set forth in the appended claims.  
         [0020]     Although the invention is illustrated and described herein as embodied in an electrical plug-in connector, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.  
         [0021]     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]      FIGS. 1-3  are diagrammatic, perspective views of a plug part of a device connection plug according to the invention;  
         [0023]      FIGS. 4-6  are diagrammatic, perspective views of a socket part of the device connection plug;  
         [0024]      FIGS. 7-9  are diagrammatic, perspective views of a plug part of a cable plug-in connector;  
         [0025]      FIG. 10  is a diagrammatic, perspective view of a strain-relief device for the cable plug-in connector;  
         [0026]      FIGS. 11-13  are diagrammatic, perspective views of a socket part of the cable plug-in connector;  
         [0027]      FIG. 14  is a diagrammatic, perspective view of an opener for a connection mechanism;  
         [0028]      FIG. 15  is a diagrammatic, perspective view of a socket part having a locking tongue;  
         [0029]      FIG. 16  is a diagrammatic, perspective view of the socket part having an opener snapped on;  
         [0030]      FIG. 17  is a diagrammatic, plan view of the plug-in face of a plug with encoding and protection against rotation;  
         [0031]      FIG. 18  is a diagrammatic, plan view of the plug-in face of a socket relating to the plug shown in  FIG. 17 ;  
         [0032]      FIGS. 19A-19M  are schematic illustrations of the possible encodings in the case of the plug shown in  FIG. 17 ; and  
         [0033]      FIGS. 20-21  are diagrammatic, sectional views of further exemplary embodiments. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0034]     Referring now to the figures of the drawing in detail and first, particularly, to  FIGS. 1-3  thereof, there is shown an embodiment of a plug-in connector according to the invention as a device connection plug. Here, a three-pole (N, L, ground) round plug-in connector  1 , in the form of a plug part, is shown which has already been fitted in a mounting opening of a device wall  2 . The plug-in connector according to the invention, however, may also be configured to have, for example, five poles or any desired number of poles. The three plug pins  5 , which are disposed parallel to one another, are each surrounded by a contact-protection sleeve  6 , which protrudes beyond the pin contacts, on a front end side  3  of a cylindrical contact carrier  4  of the plug-in connector  1 . The contact-protection sleeves  6  are surrounded by a casing  7 , which is generally triangular in cross section and, which is integrally formed on the contact carrier  4  of the plug-in connector  1 .  
         [0035]     For mounting on the device wall  2 , the contact carrier  4  has a circumferential stop collar  8 . In order to seal the plug-in connector  1  to the housing wall  2 , an axial seal  9 , for example in the form of a sealing ring, which is clad on one side with an adhesive film, is fitted to the stop collar  8 . The plug-in connector  1  is inserted into the housing opening from a housing interior  10  and is fixed externally on the device wall  2  with the aid of a fixing nut  11 . When the fixing nut  11  is tightened, the sealing ring  9  is then compressed, and seals the mounting opening. A corresponding external thread  12  is fitted to the contact carrier  4  in the region of the stop collar  8 .  
         [0036]     As depicted in  FIG. 2 , which illustrates the plug-in connector  1  without the housing wall, a contact region  14  is provided on a rear end side  13 , which is opposite the front end side  3 , of the plug-in connector  1  for the purpose of connecting the non-illustrated conductors. The connection region  14  has push-in contacts  15  in the form of spring-force terminals. It is thus possible, for example, to connect single-wire or finely stranded conductors having a cross-sectional connection area of 0.75 to 2.5 mm*mm. Contacts  15  are in this case in the form of twin contacts, with the result that in each case two conductor ends can be connected to one pole.  
         [0037]     In order to form a reliable connection to the corresponding socket part, a locking tongue  16  is provided which can be inserted into a longitudinal shaft  18 , which extends in the plug-in direction  17 , in the plug housing  4 , and whose locking hook  19 , which is fitted at one end, engages in a correspondingly provided locking window  20  to provide a secure fixing, see  FIG. 3 , which shows the plug-in connector  1  without a nut and locking tongue. The locking tongue  16  can in this case be plugged in either loosely or else as an already preassembled component on the plug or socket part. However, it is also possible for the locking tongue  16  to be in the form of an integral component of the contact carrier  4 .  
         [0038]     Directly at the foot of the covering  7 , a radial seal  21  is applied around the external covering  7  of the contact-protection sleeves  6 . The radial seal  21  extends into a correspondingly provided accommodating groove  22 . In this case, a conventional  0 -ring may be used as the radial seal  21 , which in this case assumes the triangular form of the protective covering  7  when it is applied.  
         [0039]      FIG. 4  shows a socket part  23 , which corresponds to the just-described plug part  1 , of a round plug-in connector. The socket part  23  can also be mounted in the housing opening of the device wall  2  with the aid of a fixing nut  11 . In order to seal the plug-in connector  23  to the device wall  2 , in turn an axial seal is provided on the stop collar  8 . The connection region  14 , which is fitted at the rear, is provided with twin connections  15  in the form of spring-force terminals, just as in the case of the plug part  1 .  
         [0040]     The plug face lying on the front side  3  in turn has three contact-protection sleeves  24 , which surround the three contact sockets  25  (N, L, ground). A covering  26 , which is in turn essentially triangular in cross section, is disposed around the contact-protection sleeves  24 . However, the protective casing  26 , in contrast to the above-described plug part  1 , does not protrude beyond the front end side  3  of the contact carrier  4 , but ends with it. Even the socket part  23  has a longitudinal shaft  18 , which extends in the plug-in direction  17 , for the purpose of accommodating a locking tongue and corresponding locking windows for latching the latching hooks.  
         [0041]     In a further embodiment of the invention, the plug-in connector is in the form of a cable plug-in connector. In FIGS.  7  to  9 , here in turn a three-pole embodiment of a corresponding plug part  27  is shown. A strain-relief device  28 , which is fixed with the aid of a union nut  29 , is fitted to the rear side, which lies opposite the end side  3  of the contact carrier  4 . The end side  3  having the plug contacts  5 , the contact-protection sleeves  6  and the radial seal  21  as well as the corresponding locking elements  18 ,  20  is in this case of identical configuration to the above-described device connection plug  1 ,  23 . However, the plug-in connector housing  4  now has additional latching elements in the form of latching hooks  30  for the purpose of producing a latching or snap connection to the strain-relief device  28 .  
         [0042]     In order to seal the connection between the contact carrier  4  and the strain-relief device  28 , a circumferential radial seal  31  is provided on the contact carrier  4  and is inserted in a correspondingly circumferential groove  32  and held therein. When the strain-relief device  28  is latched onto the contact carrier  4 , the radial seal  31  is then located in the region of overlap and seals the two parts  4 ,  28  with respect to one another.  
         [0043]     The strain-relief device  28  which is in the form of a kind of sleeve (see  FIG. 10 ) has, on its front end side  33 , three latching recesses  34 , which are disposed offset with respect to one another and which are in the form of grips. When the strain-relief device  28  is pushed axially onto the contact carrier  4 , in this case three latching elements  30 , which are disposed symmetrically at the rear on the circumference of the contact carrier  4 , engage in the latching recesses  34  in the strain-relief device  28 .  
         [0044]     The strain-relief device  28  tapers, starting from its front side, in the direction of its rear side with a plurality of steps (see  FIG. 10 ) and has, at its rear end  35 , a lamella-like holding apparatus  36  for the purpose of fixing the non-illustrated cable. A cable seal  37  lies in the strain-relief device  28  for the purpose of additionally sealing the plug-in connector  27  to the cable to be connected. The strain-relief device  28  is fixed with the aid of a fixing nut  29 , which is screwed onto the rear of the strain-relief device  28 . For this purpose, the strain-relief device  28  has a corresponding external thread. The fixing nut  29 , just as the fixing nut  11  for the purpose of fixing the plug-in connector  1 ,  23  to a device wall, may be provided with a mechanism which prevent the possibility of screwing by hand. The mechanism may be, for example, ratchet-like latching hooks.  
         [0045]     For the purpose of connecting the plug-in connector  27 , first the strain-relief device  28  and the cable seal  37  are pulled over the cable. Then, the cables, from which insulation has been stripped, are connected to the spring-force terminals  15 , and the strain-relief device  28  is connected to the contact carrier  4  by being latched on axially. FIGS.  11  to  13  show a corresponding socket part  39  of the cable plug-in connector.  
         [0046]     The plug-in connectors  1 ,  23 ,  27 ,  39  described can be plugged to one another so as to form socket/plug combinations. It is thus possible, for example, for the plug part  27  (shown in  FIG. 7 ) of the cable plug-in connector to be connected to the socket part  23  (shown in  FIG. 4 ) of a device connection plug etc. When the socket and plug parts are connected, the respective contact-protection sleeves  7 ,  26  are pushed one inside the other. In this case, the inner side of the protective covering  26  of the socket part  23 ,  39  then bears against the outer side of the covering  7  of the plug part  1 ,  27 , with the result that the radial seal  21  fitted to the plug part  1 ,  27  seals the socket and plug parts with respect to one another.  
         [0047]     An opener  40  for the purpose of opening the locking is shown in  FIG. 14 . The opener  40  has an at least semi-circular ring segment  41  for the purpose of fixing it to the contact carrier  4 , snap hooks  42  being fitted to the ends of the ring segment  41 . A release knob  44  is fitted to the ring segment  41  via a resilient web  43 . An actuating surface  45  is fitted to that side of the web  43 , which lies opposite the release knob  44 . For the purpose of fixing the opener  40  to the contact carrier  4 , the contact carrier  4 , as illustrated in  FIG. 15 , has an accommodating groove  48 , which is formed on its front end side by an inner ring  46  and an outer ring  47 . When mounted, the inner and outer rings  46 ,  47  at the same time serve the purpose of absorbing the forces produced on actuation of the opener  40 .  
         [0048]     The accommodating groove  48  has at least two latching recesses  49  for the purpose of accommodating the snap hooks  42  of the opener  40 . The inner ring  46  has an aperture  50  in the region of the locking window  20  for the purpose of accommodating the opener web  43 , which, when mounted, extends from the accommodating groove  48  to the locking window  20 .  
         [0049]     As illustrated in  FIG. 16 , the opener  40  is in the latched state disposed on the contact carrier  4  such that the release knob  44  points into the locking window  19  without it coming into contact with the locking tongue  16 ,  19 . On actuation of the opener  40 , by the web  43  being deflected from its rest position, for example, owing to the pressure of a finger on the actuating surface  45 , the relief knob  44  moves into the locking window  19  and pushes the latching hook  19  of the locking tongue  16  out of its locked position. It is then possible for the locking to be separated owing to the socket and plug parts being drawn away from one another in the axial direction.  
         [0050]      FIGS. 17 and 18  show plug faces  51 ,  52  of plug contacts associated with one another. In this case, encoding pins  53 ,  54  which are inserted in corresponding encoding pin recesses  55 ,  56 , in the form of cutouts, in the plug part  27  when the socket part  23  and the plug part  27  are plugged together, are integrally formed on the contact-protection sleeves  24  of the socket contacts  25 . In this case, the encoding pins  53 ,  54  are integrally formed on the contact-protection sleeves  24  of the socket part  23 , whereas the contact-protection sleeves  6  of the plug part  27  have corresponding pocket-like extensions  55 ,  56 .  
         [0051]     In the case of the three-pole plug-in connector illustrated, there is a total of 12 different encoding possibilities. These are illustrated schematically in  FIGS. 19A-19M .  
         [0052]     In this case, the variant shown in  FIG. 19A  corresponds to the plug face shown in  FIG. 17 . One factor which remains the same in all of the encoding variants is the pin  57 , which points in the center point of the three plug-in contacts, on the socket part  23  which, together with a corresponding recess  58  in the plug part  27 , provides protection against rotation.  
         [0053]      FIG. 20  shows a very simplified sectional view of a two-part device connection plug corresponding to a preferred embodiment of the invention. The device connection plug has all of the features described above which are critical to the invention, as are also illustrated in FIGS.  1  to  6 . In addition, the plug-in connector in this embodiment has an adapter element  101  which can be connected to the contact carrier. The adapter element  101  contains a sleeve-like base body  102 , for example made from a plastic material, on one side of which there is integrally formed a tubular connection or attachment piece in the form of a bushing connection piece  103 . A central longitudinal axis  104  of the base body  102  in this case corresponds to a central longitudinal axis  105  of the bushing connection piece  103 , with the result that the bushing connection piece  103  extends in a straight line away from the base body  102 . On that side of the base body  102  that lies opposite the bushing connection piece  103 , the base body  102  has an accommodating opening  106  for a contact carrier. The contact carrier may be either a plug contact or else a socket contact. By way of example, a schematic illustration of a corresponding plug contact  107  is depicted. The plug contact  107  has, for the purpose of forming a releasable connection, connecting elements in the form of latching tongues  108 , which latch into corresponding latching recesses  109  in the base body  102  of the adapter element  101  and, when the contact carrier  107  and the adapter element  101  are joined together, form a secure, mechanical connection. The bushing connection piece  103  is configured to be hollow on the inside, with the result that electrical connection cables can be passed through the bushing connection piece  103  and the base body  102  to the contact carrier  107  and can be connected there to the contact elements of the plug contact. A screw thread  110  is fitted to the outer circumference of the bushing connection piece  103 . A fixing nut  111 , which is fitted to the bushing connection piece  103 , serves the purpose of mounting the adapter element  101  in a housing opening  112  in a housing wall  113 . In other words, the adapter element  101  is fixed with its rear side  114 , which faces away from the contact carrier  107 , to the housing wall  113 . In order to ensure effective sealing of the plug-in connection, a round seal  115  is provided which surrounds the bushing connection piece  103  and bears against the base body rear side  114 .  
         [0054]     Whereas conventional plug-in connector housings are configured, for example, to be mounted in an M 25 mounting opening, the bushing connection piece  103  has a smaller diameter in the exemplary embodiment, with the result that it is also possible for mounting to be performed in a housing opening  112  for M 20 threads (corresponding to PG 13.5).  
         [0055]      FIG. 21  shows an again very simplified sectional view of a further exemplary embodiment of an adapter element  101 . Here, by way of example, a socket contact  117  is illustrated as the contact carrier to be connected. The adapter element  116  differs from the above-described adapter element  101  by the fact that the bushing connection piece  103  is fitted to the base body  102  of the adapter element  116  such that it is bent back at an angle. The central longitudinal axis  105  of the bushing connection piece  103  encloses, with the central longitudinal axis  104  of the base body  102 , an angle a of approximately 30°. Other adapter elements may have a different connection angle in the range from 90° to 180°. Corresponding to the position of the housing opening  112  or the housing wall  113 , the rear side  114  of the base body  102  extends at an angle to the base body central axis  104 .  
         [0056]     This application claims the priority, under 35 U.S.C. § 119, of German patent application No. 102 46 450.2, filed Oct. 4, 2002; the entire disclosure of the prior application is herewith incorporated by reference.