Patent Abstract:
The plug ( 10 ) comprises first ( 10 ′) and second ( 10 ″) portions, wherein said second portion is arrangeable in the cylindrical cavity of a socket, a sleeve ( 12 ) consisting of first ( 12 ′) and second ( 12 ″) parts and an abutment element ( 11 ) for blocking the sleeve ( 12 ) displacement in the cylindrical cavity direction. Said abutment element ( 11 ) and the plug ( 10 ) are embodied in one piece and said second part ( 12 ″) of the sleeve is selected such that it is flexible in order to enable the sleeve ( 12 ) to be displaceable over the abutment element ( 11 ).

Full Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of sealed, lockable connectors of the “push-pull” type. 
         [0002]    Such connectors are known in the prior art, for example from publications EP 1 577 985, U.S. Pat. No. 6,290,525 B1 and EP 0 875 959. In the connector described in EP 1 577 985, a particular mechanism makes it possible to lock the two parts of the connector together and therefore prevent an inadvertent disconnection if the cable is pulled. Accordingly, this publication is incorporated by reference into the present application with respect to the elements used for the operation of a locking system. 
         [0003]    More particularly, this type of connector is characterized by a series of elastic strips fixedly attached to the end of a movable sleeve that covers the body of one of the two connector elements. Once the connector is closed, the strips are housed between the body of the element that they surround and the external part of the second connector element. The end of the body comprises a conical ramp designed to act on the ends of the strips to cause them to spread apart when axial forces act on the male and female part of the connector to separate them, thereby preventing this separation. 
         [0004]    A disadvantage resulting from the principles currently used lies in the fact that the strips are greatly acted upon when lateral forces are exerted on the connector, for example during pulls or oscillations applied to the cable. Because of the space made beneath the strips to allow them to bend back during unlocking, the strips progressively sustain a crushing action which may promote an accidental unlocking of the connector. 
         [0005]    One solution for remedying this problem consists in reducing the length of the slots situated between the strips or, alternatively, in increasing the width of the strips, in order to make the latter more rigid, hence more resistant to the crushing actions. This approach is however unsatisfactory because it then makes the disconnection of the connector more difficult. 
         [0006]      FIG. 1  represents, as an example, a connector of the “push-pull” type combining both a locking mechanism and a seal against fluids. This type of design has been used for a long time in many applications as indicated above. 
         [0007]    More particularly, in  FIG. 1 , that illustrates a connector of the prior art as indicated above, there are mainly three elements that will be useful for understanding the invention. Naturally, for a more detailed description of this type of connector, reference may be made to the publications of the prior art indicated at the beginning of the present description. Thus, the connector comprises in particular in zone  1 , that is that of the cable  6 , a tubular body  1  forming, with a locking sleeve  2  that can be moved axially on the body  1 , the male part  5 , and serves to perform the locking action. At the end of the body  1 , there is a tubular casing  3  that is attached to said body in the manners indicated below, the whole assembly belonging to the male part  5 . On the right of  FIG. 1 , in zone  2 , there is the female part  4  of the connector into which the male part  5  is inserted. 
         [0008]    The need to be able to adapt these connectors to cables with varying dimensions means that the rear zone of the connector (zone  1 ) is most frequently substantially larger in diameter than the interconnection part (zone  2 ) which frequently must, on the other hand, be small for imperatives of space requirement of the connector base usually situated on a device. 
         [0009]    From these geometric considerations it follows that the mounting of the components is conventionally and necessarily carried out in the sequence represented in  FIG. 2  from which follows a necessary sealing of the tubular casing  3 . 
         [0010]    Sealing is an operation that is usually costly and may, depending on the chosen method, require a test to verify the seal. 
         [0011]      FIG. 2  illustrates the sequence A and B for mounting the three elements  1  to  3  identified above and belonging to the male part  5 . Because of the diameter, dimension, size constraints, it is understood that first of all the locking sleeve  2  is inserted onto the body  1 , said sleeve comprising a locking part  2   a  (for example strips) whose diameter must be smaller than the diameter of the tubular casing  3  in order to ensure that the locking mechanism operates, according to the known principles for such connectors of the “push-pull” type (see the publications mentioned above). The tubular casing  3  is therefore fitted last in the mounting sequence and it serves to spread apart the strips of the locking part  2   a  of the sleeve  2  as is known in the prior art. Consequently, the join of the tubular casing  3  on the body  1  must be sealed, which may be done by various means, for example with seals, or with the aid of adhesives or else via a welding process or else by mechanical deformation, or even driving. 
         [0012]    In addition to the complication and added cost generated by this additional operation for mounting the tubular casing  3 , another disadvantage is the fact that, once mounted, the device can no longer be removed without separating the tubular casing  3  from the body  1  which may cause damage and even the destruction of the pieces  1  and/or  3 . 
         [0013]    A solution to this problem has been described in patent U.S. Pat. No. 6,290,525. In the connector described in this patent, on the one hand a tubular casing with a plurality of “bosses” is provided and, on the other hand, slots are left between the strips of the sleeve at least as wide as the width of the bosses of the tubular casing. Therefore, it is possible to insert the tubular casing into the sleeve via the proximal end by causing the bosses to enter the corresponding slots between the strips, then a relative rotation of the two pieces is carried out so that the strips are in line with the bosses and the locking mechanism operates. 
         [0014]    It is easy to understand that this system is not optimal in that it is necessary to manufacture a particular tubular casing with bosses; during mounting, it is necessary again to carry out a relative rotation of the two pieces so that the locking mechanism operates, this particular position having to be maintained by additional means when the connector is operating. In other words, this complicates the manufacture of the pieces and the mounting procedure and one runs the risk that the locked state is not held. 
         [0015]    By convention, in the present application, the word “plug” will designate the male part of the connector and the word “socket” the female part of the connector. 
       SUMMARY OF THE INVENTION 
       [0016]    One objective of the invention is to remedy the problem of cost by removing the need to seal parts, and hence to test them. 
         [0017]    Another objective of the invention is to improve the known connectors. 
         [0018]    More particularly, one object of the invention is to propose a connector that is effective and easy to produce without substantially increasing the cost. 
         [0019]    Another object of the invention is to propose a connector system that is easy to use and that retains the locking and sealing properties of the connector. 
         [0020]    These objects are achieved by the connector defined in the claims. 
         [0021]    The invention will be better understood through the description of the embodiments of the latter given as nonlimiting illustrative examples and the figures relating thereto. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES  
         [0022]      FIG. 1  illustrates in section an example of a “push-pull” connector of the prior art. 
           [0023]      FIG. 2  illustrates side views of the mounting sequence (sequence A and B) of the plug of a connector similar to that of  FIG. 1 . 
           [0024]      FIG. 3  illustrates side views in section of the mounting sequence of the plug of a connector according to the invention. 
           [0025]      FIG. 4  illustrates a second embodiment of the connector. 
           [0026]      FIG. 5  illustrates a third embodiment of the connector. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]    According to the invention and as shown in the sequences A to D of  FIG. 3 , the body  10  forming the plug comprises a first cylindrical portion  10 ′ and a second cylindrical portion  10 ″. It also comprises at its end a profile  11  exactly matching the shape of the tubular casing  3  previously used (see  FIGS. 1 and 2 ). The tubular casing  3  is therefore no longer required here since it is replaced by the profile  11  that forms part of the body  10 . 
         [0028]    The sleeve  12 , for its part, comprises a first part  12 ′ designed to surround the first part  10 ′ of the body  10  and a second part  12 ″, designed to surround the second part  10 ″ of the body  10 , comprising strips separated by slots  13  and performing the locking function as described above. 
         [0029]    In order to be able to mount the locking sleeve  12  despite the presence of the profile  11 , it is made diametrically elastic, for example by lengthening the slots  13  or increasing their number, so it can be assembled onto the body  10  by deforming diametrically when it passes over the profile  11 , as illustrated schematically in  FIG. 3 , sequence B. 
         [0030]    The end of the sleeve  12  comprises bosses  14  on the strips forming the part  12 ″ that make it possible to perform the function of locking the mounted connector, in a manner known in the prior art. 
         [0031]    After the sleeve  12  has been installed (see  FIG. 3 , sequence C), an additional, optional piece  15  makes it possible on the one hand to stiffen the sleeve  12  and to perform all the technical and ergonomic functions of the conventional sleeve  2  described above particularly for the unlocking of the connector. 
         [0032]    The piece  15  may or may not be required and its features dictated amongst other things by the choice of the materials forming in particular the sleeve  12 . Once assembled (see  FIG. 3 , sequence D) the plug has the same features as its conventional version of  FIG. 1 . 
         [0033]    As indicated above, the sleeve  12  is made diametrically elastic to allow it to be mounted, this elasticity being obtained either by lengthening the slots  13  for example over the major part of the axial length of the sleeve  12 , or else by increasing the number of slots, or else by combining these two procedures. 
         [0034]    According to one variant, it is possible to extend one of the slots  13  over the whole length of the sleeve  12 . In this case, the additional piece  15  is necessary to “close” the sleeve  12  and prevent it from separating from the plug  10 . 
         [0035]    Since the tubular casing according to the invention does not have the principle of the bosses as taught in patent U.S. Pat. No. 6,290,525, all their disadvantages are avoided: more complicated manufacture, particular mounting, reduced number of locking strips, etc. This known tubular casing does not make it possible to ensure the seal because this part is cut, consequently is not leaktight on a seal placed as indicated in  FIG. 1  of the present application. 
         [0036]    According to another embodiment of the invention, represented in  FIG. 4  by the mounting sequence A to D, means are provided for limiting the travel of the sleeve relative to the plug. The plug  20  comprises a first cylindrical portion  20 ′ and a second cylindrical portion  20 ″ of lesser diameter. The part  20 ′ comprises an annular groove  21  extending over the periphery of the plug in which an annular element  22  of the sleeve  23  is designed to nest to limit the travel of the sleeve  23  in the axial direction. The first portion  20 ′ also comprises an axial notch  24  that extends in the body  20 ′″ of the plug  20 . The sleeve also comprises an axial extension  25  of a shape matching the notch  24  which, once the sleeve  23  is mounted on the plug  20 , makes it possible to prevent a relative rotation of these two elements. It is therefore possible to easily orient the plug  20  relative to the socket  4  (see  FIG. 1 ) in order to align the contacts at the moment of connection by rotating the sleeve. 
         [0037]    It should be noted that the groove  21  and the annular element  22  may be inverted. Similarly, it is also possible to invert the notch  24  and the extension  25 . 
         [0038]    In this embodiment, it may be useful to add an additional piece  29  similar to the piece  15  of the first embodiment described above and for the same reasons, particularly stiffening the sleeve  23 , or if one of the slots  28  extends over the whole length of the sleeve  23 . 
         [0039]      FIG. 5  shows the mounting sequence A to D of another embodiment of the invention. In this embodiment, the plug  30  comprises a first portion  30 ′ and a second portion  30 ″ of reduced diameter. The first portion also comprises at least one cavity  31  (two cavities are shown in  FIG. 5 ) that is designed to receive a protuberance  32  of the sleeve  33 . By the use of one (or more) cavity(ies)  31  and of the corresponding protuberance(s)  32 , it is possible via this single means to ensure a limitation of the axial travel of the sleeve  33  and provide a rotational lock. It is therefore possible to dispense with the notch  24  and with the extension  25  of the embodiment described above in relation to  FIG. 4 . 
         [0040]    The mounting sequence A, B and C of  FIG. 5  applies the same principles as the corresponding sequence of  FIG. 3 . 
         [0041]    Once the sleeve  33  is correctly mounted and the protuberance(s)  32  is/are in their cavity  31  (see  FIG. 5 , sequence C), it is possible to add an additional piece  37  identical to the piece  29  of the preceding embodiment or  15  of the first embodiment. This optional piece makes it easier to move the sleeve  33  on the plug  30  and to stiffen the sleeve  33 . 
         [0042]    The mounted state is shown schematically in the sequence D of  FIG. 5 . 
         [0043]    According to a variant, applicable to all the embodiments described above, it is also possible to extend only one of the slots  13 / 28 / 36  over the whole length of the sleeve  12 / 23 / 33  to make its mounting still easier. In this case, it is necessary to use a supplementary means to ensure the closure of the sleeve once mounted, for example adhesive, or else by means of the additional piece  15 / 29 / 37  which is slid over the sleeve  12 / 23 / 33 . 
         [0044]    The materials used for the sleeve  12 / 23 / 33 , and for the additional piece  15 / 29 / 37 , may be metal or plastic or else other materials such as composites etc. The additional piece may be driven onto the sleeve or bonded or attached by another equivalent means. 
         [0045]    The advantages of the invention are as follows:
   No sealing of the tubular casing  11 =reduction of costs   Fusion of the pieces  10  and  11  into a single piece=seal ensured and independent of the mounting process   Increased flexibility in the choice of the materials and the shapes of the pieces; esthetic, ergonomic and functional advantages.

Technology Classification (CPC): 7