Abstract:
A plug connection, including a plug connector and a socket for an implantable medical device, and further including a sealing element which is sheared along the axis of the plug connector and which seals the lumen formed by the socket and the proximal end of the plug connector against the environment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the priority of German Patent Application No. DE 10 2009 002 398.4, filed on Apr. 15, 2009 in the German Patent Office, the disclosure of which is incorporated herein in its entirety by reference. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to a sealing element and a plug connection with a sealing element which can be used on or in an implanted medical device (“IMD”) and which has a reduced mechanical joining resistance when joining plug connector and socket. 
       BACKGROUND OF THE INVENTION 
       [0003]    Known sealing elements and plug connections have the disadvantage that peak forces occur when joining the plug connector and socket and, in particular, when the static friction must be overcome when the sealing element, or the sealing elements, abut against their assigned sealing faces and the frequently occurring required deformation energy for passing the entrance openings of the sealing faces must be applied. In case of the IMDs, such peak forces can cause damage to the plug connector, the socket and/or the lines attached to the plug connector (for example, by bending the line). 
         [0004]    In the following, the term “static friction” is to be understood as the static friction and/or the force that is necessary to deform the sealing element. Also, the sealing element is not limited to a simple sealing element, but can relate to the sealing part of a larger structure. 
         [0005]    Previous solutions optimize primarily the sealing capability of the sealing elements, typically by minimizing the sealing face, and address the joining only to the extent that outer edges or inner edges of the sealing elements are rounded and/or that friction-reducing additives and/or coatings are used. 
         [0006]    The present invention is directed towards overcoming one or more of the above-identified problems. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is intended to provide an optimized sealing element and an optimized plug connection with the sealing element which are optimized with respect to preventing peak forces during joining. 
         [0008]    According to the present invention, a sealing element for sealing plug connections of an implanted medical device (“IMD”) is provided, wherein the sealing element has a first expansion in one plane, and a second expansion perpendicular to the plane, and has an opening within this plane, which opening extends over the second expansion, and wherein the sealing element is sheared. 
         [0009]    The phrasing “sheared” refers to one or more shearings, and or elongations, and/or displacements of the basic shape. The sealing element can be manufactured in such a manner that it has the sheared shape without application of a force, or that it can be formed into this shape by applying a force. The term “plug connection” includes electrical plug connections as well as plug connection for hollow lines, such as, for example, for liquids. 
         [0010]    Furthermore, the sealing element can be sheared in such a manner that a segment of the sheared sealing element runs parallel to the second expansion. In a preferred embodiment, the sealing element can have the shape of a sealing ring which is sheared parallel to a second expansion. 
         [0011]    In a further preferred embodiment, the sealing element consists of an elastic material with a Shore hardness between 15 ShA and 80 ShA, according to DIN 53505 and DIN 7868. 
         [0012]    In a particularly preferred embodiment, the sealing element consists of an elastomer and/or polymer, preferably from silicone rubber or latex, polyurethane, or polyurethane-copolymer with silicone content. 
         [0013]    In a further preferred embodiment, the sealing element is provided with a hydrophobic and/or hydrophilic coating for reducing the sliding friction. 
         [0014]    In addition, according to the present invention, a plug connection for an IMD is provided, including a plug connector and a socket with a sheared sealing element which seals a lumen formed by the socket and the proximal end of the plug connector against the environment. The sealing element can be designed according to any one of the above described embodiments. 
         [0015]    In a preferred embodiment, the sealing element can sit on the plug connector or within the socket in a recess which is suitable to receive the sealing partially and to securely locate it on the plug connector or within the socket. Alternatively, the sealing element can also be part of a larger element, and the larger element securely locates the sealing element on the plug connector or within the socket. In addition, the plug connection can be designed in such a manner that a segment of the sheared sealing element runs parallel to the longitudinal axis of the plug connector. 
         [0016]    In a particularly preferred embodiment, the plug connector has a cylindrical shape and the sheared sealing element has the shape of a sheared sealing ring. In a further particularly preferred embodiment, the plug connection has two or more sealing elements which are sheared along the axis of the plug connection and which seal the lumen formed by the socket and the proximal end of the plug connector and the lumen, or the lumens, between the sealing elements against the environment. It is also preferred that the plug connection has two or more sealing elements, wherein the position of the sealing elements on the plug connector or within the socket is configured in such a manner that the sealing elements, during insertion of the plug connector into the socket, come into contact with their assigned sealing face of the socket or the plug connector with a time difference. 
         [0017]    It is particularly preferred that the time difference is configured in such a manner that during joining, a sealing element touches the distal end of its assigned sealing face only when the previously inserted sealing element has completely passed the distal end of its assigned sealing face. Alternately, the time difference can be configured in such a manner that a sealing face of a plug connector touches the distal end of its assigned sealing element only when the previously inserted sealing face has completely passed the proximal end of its assigned sealing element. 
         [0018]    Other objects, aspects and advantages of the present invention can be obtained from a study of the specification, the drawings, and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    Embodiments of the present invention are described in an exemplary manner with reference to the attached drawings. In the Figures: 
           [0020]      FIG. 1A  shows a side view of a plug connector with two sealing elements known as prior art; 
           [0021]      FIG. 1B  shows the forces to be overcome when joining a prior art plug connector with respect to the distance covered during joining; 
           [0022]      FIG. 2A  shows an embodiment according to the invention of a plug connection with a sheared sealing element; 
           [0023]      FIG. 2B  shows a sheared sealing ring according to the invention; 
           [0024]      FIG. 2C  shows the forces to be overcome when inserting a plug connector into a socket having a sealing element according to the invention as shown in  FIG. 2A  with respect to the distance covered during joining; 
           [0025]      FIG. 3A  shows an embodiment according to the invention of a plug connection with two sheared sealing elements; 
           [0026]      FIG. 3B  shows the forces to be overcome when joining a plug connector having sealing elements according to the invention as shown in  FIG. 3A  with respect to the distance covered during joining; 
           [0027]      FIG. 4A  shows an embodiment according to the invention of a plug connection with a sealing element which is sheared in two areas and elongated in one area; 
           [0028]      FIG. 4B  shows the forces to be overcome when joining a plug connector having a sealing element according to the invention as shown in  FIG. 4A  with respect to the distance covered during joining; 
           [0029]      FIG. 5A  shows an embodiment according to the invention of a plug connection with two sheared sealing elements with different diameters on a plug connector with different diameters; 
           [0030]      FIG. 5B  shows the forces to be overcome when joining a plug connector having sealing elements according to the invention as shown in  FIG. 5A  with respect to the distance covered during joining; and 
           [0031]      FIG. 6  shows an embodiment according to the invention of a plug connection with two sheared sealing elements with different diameters within a socket with two different diameters. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Provided is a sealing element and a plug connection with at least one sealing element. For illustration purposes only, the sealing elements are shown as sealing rings and the plug connection is shown as a cylindrical plug connector with a cylindrical socket; however, they can also be provided in any other shape such as, but not limited to, sealing disks or polygonal sealing disks, or polygonal sealing rings, or polygonal plug connectors and/or sockets. Also, for a better understanding, the illustration of more than two sealing elements is omitted, wherein it is apparent for a person skilled in the art that, for example, for multi-pole plug connections perhaps more sealing elements may be required. 
         [0033]    Known from the prior art is a plug connection, as shown in  FIG. 1A . In  FIG. 1A , two ring seals  12  and  13  are sitting on a plug connector  10 . The proximal end of the plug connector is inserted into the socket  11  in direction of arrow  10   a.  The peak forces to be overcome herein are illustrated in  FIG. 1B . The forces to be overcome are plotted against the travel distance of the plug connector  10  within the socket  11 . The occurring peak forces  15  and  17  are generated by the static friction to be overcome and by deformation forces which are generated when the sealing elements are pressed into the sealing faces  14  of the socket  11 . The drops  16  and  18  are generated due to the disappearance of the forces to be applied for the deformation and due to the disappearance of the static friction after the complete insertion of the respective sealing element  12  or  13  into the sealing faces  14 . 
         [0034]    A plug connection according to the present invention with a sealing element according to the invention is shown in  FIG. 2A . The plug connector  20  is inserted with the proximal end  20   a  into the socket  11 . The sealing element  21  is sheared along the longitudinal axis of the plug connector  20  in such a manner that first the proximal end of the sealing element  21   b  touches the sealing face  14  when inserting the proximal end of the plug connector  20   a  into the socket  11 , and that the rest of the sealing element  21   a  comes in contact with the sealing face  14  only after further insertion, and that the distal end of the sealing element  21   a  passes the sealing face  14  last. 
         [0035]      FIG. 2B  shows a sealing element  21  prior to shearing. It has an opening  22 , wherein the area of the opening lies in the area of the sealing element and forms an axis perpendicular to the area of the opening, and wherein the sealing element has a constant thickness  23  at a position perpendicular to the opening. 
         [0036]    In  FIG. 2C , the force to be overcome is plotted against the travel distance of the plug connector  20  into the socket  11 , wherein the point  24  indicates the moment when the proximal section of sealing element  21   b  comes into contact with the sealing face  14 , and the point  25  indicates the complete insertion of the distal end of the sealing element  21   a  into the sealing face  14 . Here, through the comparison of  FIG. 1B  with  FIG. 2C , the absence of peak forces in  FIG. 2C  is easily recognizable. 
         [0037]      FIG. 3A  shows a plug connector  30  with two sheared sealing elements  31  and  32  according to the present invention, and the socket  11  with the distal end of the sealing face  14 . In  FIG. 3B , the force to be overcome is plotted against the travel distance of the plug connector  30  into the socket  11 , wherein point  33  indicates the moment when the proximal section of the proximal sealing element  31   b  comes into contact with the sealing face  14 , point  34  indicates the complete insertion of the distal end of the sealing element  31   a  into the sealing face  14 , point  35  indicates the moment when the proximal section of the distal sealing element  32   b  comes in contact with the sealing face  14 , and point  36  indicates the complete insertion of the distal end of the sealing element  32   a  into the sealing face  14 . 
         [0038]      FIG. 4A  shows a sheared sealing element  41  according to the invention on a plug connector  40 . The sealing element  41  is sheared in the two outer areas and is elongated in the middle area in such a manner that a segment of the sealing element  41  between  41   c  and  41   d  runs generally parallel to the axis of the plug connector  40 . This arrangement results in the shape of the graph in  FIG. 4B  in which the force to be overcome is plotted against the travel distance of the plug connector  40  into the socket  11 . Point  42  of the graph represents the section of the travel in which the proximal end of the sealing element  41   b  comes into contact with the sealing face  14 , and point  43  marks the transition of the curve of the sealing element  41   c  in the area in which the sealing element runs generally parallel to the longitudinal axis of the plug connector  40 . Point  44  in turn marks the exit of the sealing element&#39;s  41  area  41   d  running generally parallel to the longitudinal axis of the plug connector  40 , and point  45  marks the complete insertion of the distal end  41   a  of the sealing element  41  into the sealing face  14 . 
         [0039]      FIG. 5A  shows a particularly preferred shape of the plug connector  50  and of the socket  55 , wherein the two sealing faces  56  and  54  have different sizes in which the respective proximal plug connector sections  50   b  and  50   a  fit. The sealing elements  51  and  52  are arranged on the respective plug connector sections  50   a  and  50   b  in such a manner that they touch the respective sealing faces  54  and  56  with their proximal ends  51   b  and  52   b  when inserting the plug connector  50  into the socket  55  with a time difference, this means, the distances A and B are selected such that the sealing elements touch their respectively assigned sealing faces at different points in time. Here, in the non-inserted state, the distance B of the proximal end  51   b  of the sealing element  51  to the distal end of the sealing face  54  is greater than or equal to the distance A of the distal end  52   a  of the sealing element  52  to the distal end of the sealing face  56 . 
         [0040]    In  FIG. 5B , the force to be overcome is plotted against the travel distance of the plug connector  50  into the socket  55 , wherein point  57  indicates the moment when the proximal section of the proximal sealing element  51   b  comes into contact with the sealing face  54 , point  58  indicates the complete insertion of the distal end  51   a  of the sealing element  51  into the sealing face  54 , point  59  indicates the moment when the proximal section of the distal element  52   b  comes into contact with the sealing face  56 , and point  60  indicates the complete insertion of the distal end  52   a  of the sealing element  52  into the sealing face  56 . 
         [0041]      FIG. 6  shows a particularly preferred shape of the plug connector  60  and of the socket  65 , wherein the two sealing faces  63   a  and  60   c  have different sizes which fit into the respective different sized socket section  65   a  and  65   b.  The sealing elements  61  and  62  are shown in  FIG. 6  only by means of the sections  61   c,    61   d  and  62   c,    62   d;  however, they run within the respective socket section  65   b  and  65   a  in a sheared manner analogous to the sealing elements  51  and  52  on the plug connector  50 , as shown and described with respect to of  FIG. 5A . The sealing elements  61  and  62  are arranged in the respective socket sections  65   b  and  65   a  in such a manner that when inserting the plug connector  60  into the socket  65 , the sealing elements  62  and  61  come into contact with the respective sealing faces  63   a  and  60   c  with a time difference similar to that previously described, as appreciated by one of ordinary skill in the art. 
         [0042]    It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teachings without departing from the spirit and scope of the present invention. The disclosed examples and embodiments are presented for purposes of illustration only and are not meant to limit the scope of the invention in any way. Therefore, it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof.