The invention relates to an implantable electromechanical plug connector with a plug part and a socket part.
In general, electromechanical plug connectors involve two components that can be inserted into each other in a mechanically detachment-resistant manner for the purpose of electrical energy and/or signal transmission and, depending on their design and use, are subject to specific operational safety-relevant requirements. In the case of implantable plug connectors, these must meet the requirements relating to active, implantable medical devices that are exposed to a continually moist environment which they should withstand undamaged in terms of moisture or water penetration into interior of the implant in question for as long as possible.
Particularly critical in known implantable plug connectors are the joining portions along which the components of the plug connector join to or into each other, usually in a positive or non-positive manner. The particular challenge when it come to designing such plug connectors consists in preventing penetration of water or moisture into and through the boundary surfaces between the plug part and socket part inside a plug connector in as long-term a manner as possible so at to avoid water or moisture coming into contact with the electrical structures contained within a plug connector. Water contact on electrically conducting lead and electrode structures, which are mostly made of metallic material, leads to irreversible manifestations of degradation and an associated impairment of the electrical and signal transmission properties. In addition, the presence of water or moisture can bring about detachment between the metallic structures contained within the plug connector and the surfaces of the plug connector components immediately surrounding them and usually consisting of polymer material, and thereby reduce the lifespan of such plug connectors.
A known electrical bushing for use in a housing of an active implantable medical device is described in document DE 10 2011 009 857 B4, the electrical connection structure of which passing through the housing wall is hermetically surrounded by a base body which clings to the housing wall in a fluid-tight manner. The electrical connection structure also opens onto an electrical connection contact within a head part designed as a socket and attached to the housing wall in a fluid-tight manner. The socket comprising at least one electrical connection structure is designed as part of a known standard plug connection.
Document EP 0 910 435 B1 sets out an electrical connection socket for an implantable cardiac pacemaker which comprises an elastically deformable insertion sleeve which in the relaxed state has a curved shape. After insertion of a straight cylindrical contact pin into the sleeve, the latter is forcibly deformed and comes into contact with the outer sides of the straight contact pin forming a largely fluid-tight connection.
Document DE 10 2012 020 260 B1 describes an implantable sub-cutaneous electrical socket as well as a related percutaneous plug which envisages one, preferably more electrical connection structures provided for contacting in corresponding funnel-shaped recesses within the socket. The implantable, subcutaneous electrical socket comprises a socket housing through which electrical supply and outlet leads pass for supplying energy and signals to at least one implanted medical device.
Document DE 20 2007 019 606 U1 describes a contact socket for the connection of an electrode lead to an implanted medical device with a socket housing that comprises a connector holder with an elongated holding space. The connector holder comprises a cast component made of a permanently elastic mass into which contact elements of electrically conductive material are inserted.
Described in document EP 0 811 397 B1 is an implantable unit with at least one contact arrangement for connecting an electrical device accommodated in a housing in a hermetically sealed manner with at least one connection cable emerging from the housing which is surrounded by a moulded body made of a non-elastic material and has a freely accessible electrode surface onto which through a pressing force a counter-contact to a continuing connection cable is brought into contact which is surrounded by an elastic material into which a rib-like elevation of the moulded body peripherally surrounding the contact area penetrates forming a positive connection.
Document JP 2013-094 456 A discloses an implantable plug connector with a plug part and socket part in which the quantity of electrical contact pins on the plug part side is applied along a cross-sectional area of the plug unit. Joining the contact pins with the contact sleeves on the socket side takes place through axial fitting into each other. The number of electrical contacts is therefore significantly limited due to a diameter of the plug connector that is as small as possible.
Document US 2005/0118887 A1 describes an implantable plug connector with a plurality of electrode contacts. On an upper side the drawer-like plug unit comprises electrode contacts which in the inserted state within the socket part are pressed by means of a clamping device acting orthogonally on the upper side against the counterelectrode surfaces arranged on the socket part. In the case of intracorporeal application of the plug connector this requires additional work and instrument use as well as the access necessary for this and space for operating the clamping device, designed in the form of an Allen screw for example.
The invention is based on the task of further developing an implantable, electromechanical plug connector with a plug part and a socket part in such a way that in the implanted state with the socket part and plug part joined to each other the plug connector should exhibit a high degree of imperviousness so that moisture-caused material degradation of electrically conductive structures present within the plug connector should be prevented. Moreover, intracoporeally the implantable plug connector should be able to be manually closed and/or opened easily and without additional joining components. Furthermore, incorrect operation and also operation-related damage to electrode structures in the interior of the plug connector should be ruled out. Finally, in spite of a compact and small three-dimensional shape of the plug connector, it should be possible to contact a plurality of electrical transmission leads with the plug connector.
The solution to the task forming the basis of the invention is set out in claim 1. Features further developing the concept according to the invention in an advantageous manner form the subject matter of the sub-claims and can be gleaned from the further description, in particular with reference to the illustrated examples of embodiment.
The implantable electromechanical plug connector according to the solution comprises a plug part and a socket part, of which the plug part comprises at least one joining portion which can be inserted completely into a unilaterally open insertion opening within the socket part and has at least one electrically insulating surface having at least one electrode body with a freely accessible electrode surface. The socket part has, inside the unilaterally open insertion opening at least one electrically insulating wall portion which laterally delimits the insertion opening at least in parts and whose surface provides at least one counterelectrode body with a freely accessible counterelectrode surface, wherein the plug part's electrically insulating lateral wall portion is orientated in such a way towards the socket part's electrically insulating surface in the joined together stage that the counterelectrode surface and electrode surface touch each other forming an electrical surface contact. In addition, the at least one electrode body on the plug side is raised in relation to the electrically isolating surface of the joining portion and/or the at least one counterelectrode body on the plug side is raised in relation to the surface of the electrically isolating wall portion. Further, at least one electrically insulating polymer layer is arranged at least in parts between the electrically insulating surface of the joining portion on the plug side and the surface of the electrically insulating wall portion on the socket side and laterally completely surrounds the mutually contacting counterelectrode surface and electrode surface.
The at least one electrically insulating polymer layer is preferably made of an elastic material, for example an electrically insulating elastomer, and is firmly joined either to the electrically insulating wall portion or to the electrically insulating surface of the joining portion.
Preferably the at least one electrically insulating polymer layer has a layer thickness which at least corresponds to an orthogonal elevation of the at least one counterelectrode body in relation to the surface of the electrically insulating wall portion or the at least one electrically insulating surface of the joining portion. In this way it is ensured on the one hand that in the joined state of the plug connector the contacting electrode and counterelectrode bodies are each fully surrounded in a contacting manner by the polymer layer, and on the other hand the polymer layer clings flatly to the surface of the electrically insulating wall portion or to the electrically insulating surface of the joining portion in a fluid-tight manner depending on whether the at least one polymer layer is applied on the plug part or the socket part side.
In order to improve or increase the blocking effect against the penetration of moisture into the plug connector, the size and shape of the joining portion, the size and shape of the insertion opening of the socket part as well as the size and shape of the electrically insulating polymer layer are matched to each other in such a way that in the state of complete insertion of the plug part's joining portion into the insertion opening of the socket part the at least one electrically insulating polymer layer is subjected to a compression force which acts between the surface of the electrically insulating wall portion and the electrically insulating surface of the joining portion. Through the compression force, the polymer layer is pressed flat with increased pressing force to the respective surface of the wall portion or surface of the joining portion, as a result of which a fluid-tight positive and non-positive connection between the polymer layer and the respective surface is formed.
A further preferred form of embodiment of the plug connector envisages matching the size and shape of the joining portion, the insertion opening, the at least one electrically insulating polymer layer and in particular the respective electrode and/or counterelectrode bodies to each other in such a way that the contacting electrode and counterelectrode surfaces are in mutual contact through the effect of pressing force. As the further embodiments, with reference to a specific example of embodiment, will show, the pressing force can preferably be dimensioned in a predefinable manner through a suitably dimensioned elevation of the at least one electrode body or counterelectrode body in relation to the respective surface.
In a further preferred form of embodiment the polymer layer has a hygroscopic material which on contact with moisture or water swells and thus increases in volume through which the compression effect on the polymer layer increases and at the same time the sealing effect is improved.
Preferably suited as material for the at least one polymer layer is polydimethylsiloxane, PDMS for short, or LPC (liquid crystal polymer) or parlylene. Alternative, biocompatible polymer or elastomer materials, such as polyimide, are of course also suitable. The aforementioned swelling effect can advantageously be brought about through incorporating hygroscopic components or compounds into the polymer layer, e.g. through the interspersion of salt crystals in a PDMS layer or through the provision of crystalloid, hygroscopic intermediate layers in a layered polymer layer composite. Also suitable as hygroscopic components are silica gel, activated clay, chemical water binders, zeolite, cellulose.
All the components of the plug connector designed according to the solution are made of biocompatible materials in order to thus comply with the medical approval conditions. Particularly suitable materials for producing the at least one electrode body and counterelectrode body are metals, such as, for example, gold, platinum or iridium or metal alloys. Instead of metallic electrode materials, it is also possible to use conductive polymer materials, such as PEDOT.
In a further preferred form of embodiment the plug part is flat or plate-shaped and has an upper and lower side. The joining portion of the plug part has a longitudinal and transverse direction, wherein the length of the joining portion in its longitudinal direction corresponds with an insertion depth of the insertion opening on the socket part side such that in the joined state the joining portion completely enters the insertion opening. Projecting out of the plug part is a plug portion, adjoining the joining portion in one piece, on which at least one electrical contact is provided, which is electrically connected to the at least one electrode surface provided in a joining portion. The at least one electrical contact acts as an electrical connection electrode to a lead wire, which, for example, is connected to the electrical contact by way of a soldered connection.
Along the inside of the insertion opening on the socket part side at least one insertion guide is provided on the wall, along which the joining portion on the socket part side slides in a forcibly guided manner during insertion. In a preferred example of embodiment the insertion guide has a first section, along which the joining portion can only be inserted in its longitudinal direction. Adjoining the first section along the insertion guide is a second, rear section, along which the joining portion can be further inserted in its longitudinal and transverse direction. By way of the second section the socket part is deflected relative to the plug part diagonally to the longitudinal insertion direction and reaches an end position with a lateral offset relative to the initial longitudinal insertion direction.
During the procedure of inserting the plug part into the socket part, in which the plug part is forcibly guided along the first section of the insertion guide, the at least one electrode body and counterelectrode body are at a lateral distance with regard to each other and do not come into mutual contact. Particularly in the case of a plurality of electrode bodies being provided on the joining portion and a corresponding number of counterelectrode bodies on at least one surface of the electrically insulating wall portion on the plug part side, the electrode surfaces of the electrode bodies provided on the plug part side slide past the counterelectrode surfaces of counterelectrodes on the socket part side in a contactless manner. Only through the diagonal or sideways movement that finalises the procedure of joining the plug part within the insertion opening do the electrode surfaces come into contact with the counterelectrode surfaces assigned to them. In this way unnecessary wear-associated oversliding and grinding between electrode and counterelectrode surfaces during the joining procedure are reduced to a minimum.
In addition there is the fact that though the sideways movement the plug part at least partially comes to rest in the end position in a so-called “undercut area” in which through appropriate designing of the plug part and socket part, penetration of moisture or water is impossible or at least made considerably more difficult. In particular, in the end position, areas of the side walls of the plug and socket part are in internal contact through which the entrance opening of the insertion opening is completely closed in a fluid-tight manner between the plug and socket part.
Essentially the socket part forms a type of insertion housing for the plug part. The housing is preferably made of a rigid, dimensionally-stable material consisting of a biocompatible material, preferably titanium or a ceramic. The housing surrounds the unilaterally open insertion opening completely so that all forces acting on the housing are distributed along closed force paths.
Preferably the at least one polymer layer is firmly joined to electrically insulating wall portion within the insertion opening of the socket part that has a freely accessible counterelectrode surface and in the area of the at least one counterelectrode surface has a recess so that the at least one counterelectrode surface is completely and seamlessly surrounded by the polymer layer.
In contrast the plug part has an electrode body projecting upwards over the electrically insulating surface of the joining portion which during insertion into the insertion opening of the socket part locally compresses the elastic polymer layer before reaching the end position and only on reaching the end position fits precisely into the recess in the polymer layer at the location of the counterelectrode surface. In this state the polymer layer clings seamlessly to the outer contour of the electrode body.
Alternative examples of embodiment are of course conceivable with two electrically insulating wall portions arranged opposite each other in the plug part on each of which a polymer layer is applied. It is also possible to firmly apply a polymer layer to the at least one electrically insulating surface in the joining portion of the plug part.
The plug connector according to the solution is also characterised by a compact and small three-dimensional shape which depending on the number of electrode and counterelectrode bodies to be provided within the plug connector can have a plug connector length and width of a few mm to a few cm.
Advantageously, at least the plug part can be produced as part of a multilayer process. Depending on the number of electrode bodies provided in the joining portion of the plug part, for which a corresponding number of electrical contacts in the plug portion must be provided, as explained above, as part of the manufacturing process electrical connection structures must be formed within the plug part. The electrical connection structures can be designed as individual electrical layers within a stack layer composite and/or in the form of strip conductors each applied separately on an intermediate layer surface, for the electrical contacting of which electrical connections to the electrical contacts and the electrode bodies must be created.
Advantageously, for manufacturing the plug part multilayer ceramic technology is used, preferably to produce low-temperature co-fired ceramics, LTCC, or high-temperature co-fired multilayer ceramics, HTCC for short. For producing the at least one electrode body raised above the electrically insulating surface of the joining portion, thick film technology can be used, with which layer depositions with layer thicknesses in the μm-range or above can be produced. Alternatively it is possible to produce the raised electrode body structures by applying a conductive film or paste over the entire area of electrically insulating surface of the joining portion, which is subsequently structured, preferably by means of laser radiation. Galvanic deposition techniques are also suitable for producing the electrode body structures.
The plug connector according to the solution is particularly suitable for the contacting of a plurality of electrode and counterelectrode bodies provided on the plug part and socket part in order to contact as many electrical transmission channels as possible with the aid of the plug connector. The electrode bodies on the plug side are thus each arranged distributed on the at least one electrically insulating surface, which on insertion of the plug part into the socket part is orientated in parallel or essentially in parallel to the insertion direction. In this way, through appropriate selection of the shape and size of this surface, sufficient space can be created for accommodating a large number of electrode bodies, without increasing the diameter of the implantable plug connector, as it must be kept as small as possible. In a suitable manner the counterelectrode bodies are also to be created and applied to the at least one electrically insulating wall portion laterally delimiting the insertion opening in parts.
In order to increase the plurality of electrode and counterelectrode bodies envisaged on the plug part and socket part even further, the plug part preferably has two electrically insulating surfaces which are opposite and orientated away from each other and preferably each comprise a plurality of electrode bodies each with a freely accessible electrode surface. Equally, within the unilaterally open insertion opening the socket part has two electrically insulating wall portions which are opposite and orientated towards each other, the surfaces of which comprise the same number of counterelectrode bodies each with a freely accessible counterelectrode surface. The electrically insulating wall portions on the socket part side are each orientated towards one of the electrically insulating surfaces of the plug part in the joined state so that the counterelectrode surfaces directly and indirectly touch the electrode surfaces. In this way miniaturised plug connectors can be produced which can connect up to 256 separate electrical transmission channels, preferably up to 50 transmission channels, to each other.
It is also conceivable to apply additional electrode bodies on a side wall area which connects the two aforementioned electrically insulating surfaces each orientated away from the other.
Further details concerning the design of the plug connector according to the solution are set out in the further description with reference to the examples of embodiment.
The invention will be described below without restricting the general inventive concept by way of examples of embodiment with reference to the drawings. Here:
a,b,c Show longitudinal sectional views through alternative plug parts,
Ways of Implementing the Invention, Commercial Use
The plug part 1 shown in
In the example of embodiment, in the joining portion 3 of the plug part 1 nine electrode bodies 6 are arranged, each having an upper electrode surface 6′. Correspondingly, in the plug portion 10 nine electrical contacts 16 are also provided on which, via, for example, soldered connections or similar electrical joining techniques, electrical supply/outlet leads 17 are fastened. The electrical contactsl6 envisaged on the plug part side are electrically connected in a suitable manner within the plug part 1 with electrode bodies 6 arranged in the joining portion 3. Plug connections are conceivable which can provide 40, 50 and more electrode bodies 6 on the surface 5.
The plug part 1 shown in
In
Firmly connected to the electrically insulating wall ports 7, the socket part 2 comprises an electrically insulating polymer layer 7 which has a polymer layer thickness 9d and comprises recesses 9′ which are each matched to the counterelectrode surfaces 8′ so that the polymer layers 9 peripherally surround the counterelectrode surfaces 8′ preferably in a flush and fluid-tight manner. Optionally, under each counterelectrode body 8, i.e. between the dimensionally stable, rigid housing 2G and each counterelectrode body 8 there is also a polymer layer 9″. In this way the counterelectrode body 8 is borne elastically relative to the housing 2G, which is advantageous in the case of force-effected contacting with a corresponding electrode body 6.
The configurations of the socket part and plug part 2, 1 are matched to each other accordingly, meaning that the number and arrangement of the counterelectrode bodies 8 provided in the socket part 2 correspond to the number and arrangement of the electrode bodies 6 applied in the plug part 1. The shape and dimensions of the insertion opening 4 within the socket part 2 are matched to each other in accordance with the shape and size of the joining portion 3 of the plug part 1. In the case of the socket part 2 illustrated in
A longitudinal section through a plug part 1 with four electrode bodies 6 applied on both the upper and lower side of the joining portion 3 is illustrated in
The plug connector 1 illustrated in
It is also conceivable to provide the plug connector 1 shown in
The plug part 1 is dimensioned in accordance the dimensioning of the socket part 2. The total thickness h of the plug part 1 in the joining areas 3 including the electrode body 6 raised above the surfaces 5, 5 is slightly smaller than the maximum opening width h′ of the insertion opening 4 within the socket part 2. In this way the polymer layers 9 are compressed on insertion of the plug part 1 into the socket part 2 shown in
In order to increase the blocking effect against the penetration of water or moisture along the side walls of the plug part and the socket part 2, additional polymer layers 9* can optionally be applied to the side wall areas within the insertion opening 4, preferably on the socket part side, see the polymer layers 9* shown by the dashed line in
Furthermore, for further improving the blocking effect the polymer layers 9 of 9* can at least in parts be combined with hygroscopic material components 19 which is the presence of moisture bind water and thereby cause the polymer layer 9, 9* to swell, see
A further alternative embodiment for configuring the plug part 1 is illustrated in
All electrode and counterelectrode bodies 6, 8 as well as the electrode and counterelectrode surfaces 6′, 8′ connected thereto can assume any three-dimensional shapes. Thus, n-angled, oval, round circumferential edges are suitable for configuring the electrode and counterelectrode surfaces 6′, 8′.
Preferably thefreely accessible electrode surfaces (6′) of the electrode bodies (6) are orientated in parallel or obliquely to the at least one electrically insulating surface (5, 5′), just as the freely accessible counterelectrode surfaces (8′) of the counterelectrode bodies (8) are orientate in parallel or obliquely to the electrically insulating wall portion (7, 7′).
Additionally or alternatively the surface normals of the electrically insulating surfaces (5, 5′) as well as of the electrically insulating wall portion (7, 7′) are each orientated orthogonally or obliquely to the insertion direction along which the joining portion of the plug part can be guided into the insertion opening (4) of the socket part (2).
In a departure from a mathematically strictly defined parallelism or or orthogonality, “oblique orientation” in the above sense should be taken to be an angle tolerance α of maximum α=±30°.
The insertion direction is predetermined by the shape and design of the plug part and socket part, and is, as shown in the further statements relating to
In
As soon as the diagonally orientated plug part-side side walls areas 1w shown in
After the end position of the plug part 1 within the socket part 2 is reached, see
For the purpose of securing or protecting against uncontrolled sliding out of the plug part from the socket part, in the insertion direction on the face end side edge of the plug part a web-like, structured projection can be applied which is brought into grip engagement with a corresponding recess on the socket part and ensures that releasing the plug part from the socket part is only possible after a specific forwards or lateral pushing of the plug part relative to the insertion direction and/or through a defined force acting perpendicularly on the structured projection.
Through the lateral offset 12 between the joining portion 3 and plug portion 10 determined by the design, the side wall portions 1w closest to the plug portion 10 adjoin the corresponding side wall portions 2w on the socket part side and each form fluid-tight sealing surfaces 20. With these design measures additional polymer layers to be applied to the side walls of the socket part and/or the plug part, as shown as an example in connection with the example of embodiment illustrated in
The shape of the plug part and socket part 1, 2 is not necessarily restricted to the three-dimensional shapes shown in the examples of embodiment.
In this way all-round fluid-tight sealing of the plug part 1 within the sock 2 is ensured.
1 Plug part
1
w Diagonally extending side wall flanks
2 Socket part
21 Socket part lateral inner wall
22 Socket part lateral inner wall
2
w Socket part diagonal wall section
3 Joining portion
31, 32 Side wall of the joining portion
3L Longitudinal direction of the plug part
3I Longitudinal direction of the joining portion
3Q Lateral direction of the joining portion
4 Insertion opening
4I Longitudinal direction of the insertion opening
5, 5′ Electrically insulating surface of the plug part
6 Electrode body
6′ Electrode surface
7 Electrically insulating wall portion
8 Counterelectrode body
8′ Counterelectrode surface
8″ Electrical connection structure
8′″ Electric supply/outlet lead
9 Polymer layer
9′ Recess
9″ Polymer layer
9* Polymer layer on side wall
10 Plug portion
11
a First section
11
b Second section
12 Lateral offset
13 Stack layer composite
14 Electrical layer areas
15 Electrically insulating layer areas
16 Electrical contacts
16′ Plug contact socket
17 Electrical supply/outlet leads
18 Insertion guide
19 Hygroscopic material
20 Fluid-tight sealing surface
h Thickness of the plug part
h′ Opening width
2G Housing
2S Electrical interface
Number | Date | Country | Kind |
---|---|---|---|
10 2016 212 332.7 | Jul 2016 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2017/066925 | 7/6/2017 | WO | 00 |