An electrical connector jack

Abstract: The invention relates to an electrical connector jack (18) with at least one disk-shaped means (20) made of an elastic, conductive material and which has one or more contact surfaces arranged to come into contact with the corresponding contact surfaces on a contact pin (37). A layer (22) of insulating, elastic material is provided on both sides of the electrically conductive material (20), the disk-shaped means (20) being devised to be elastically deformed by the contact pin (37) when the pin is inserted into the connector jack (18), so the electrically conductive material's contact surfaces and the insulating material are pressed against the corresponding contact surfaces on the contact pin, while the contact surfaces are protectively sealed by the insulating material.

Description: The present invention relates to an electrical connector jack, especially for contact with a contact pin on the proximal end of an electrode cable, connectable to an implantable heart stimulator, such as a pacemaker or defibrillator. Connectors of this kind are intended for installation in a connection section of the heart stimulator for electrical connection of a contact surface on the proximal end of the electrode cable, which is insertable into the connection part of the heart stimulator's pulse-generating electronics section. A commonly found connector for this purpose has, in principle, a metal shell into which the electrode cable's contact pin is inserted and affixed with a locking screw accessible from outside the connection section. The locking screw achieves contact between the shell and the pin at the same time as the electrode cable is axially locked in place, keeping the electrode cable from detaching from the connection section. These screws require manual action to achieve contact. Connectors for this application have been proposed which make possible automatic, forced contact between the contact pin and connector jack when the electrode pin in inserted into the connector jack. For example, US-A-4 934 366 and 5 012 807 describe such connector jack, made from a ring-shaped means, which, when the pin is inserted, is axially compressed against a corresponding contact on the pin, thereby achieving mechanical contact on all sides between the male contact pin on the electrode and the connector jack in the heart stimulator's contact section. The contact sites are sealed with separate sealing means arranged on the exterior of the contact pin end of the electrode cable and/or on the interior of the connector jack. EP-A2-0 339 877 also shows a connector jack for a pacemaker which contains electrically conductive elastomer rings making possible both forced mechanical coupling and electrical contact between contact surfaces, as well as simultaneous sealing against fluid leakage at the contact pin. Such contact rings have no well-defined contact and sealing areas, so these electrically conductive, elastic rings must be supplemented with separate sealing rings to achieve effective sealing of the contact surfaces. One object of the present invention is to propose an improved, electrical connector jack of the type in question with which discrete, resilient, electrically conductive means are pressed against the contact pin's contact surfaces to achieve simultaneous, protective sealing of distinct contact surfaces with an electrically insulating material to prevent junction corrosion at the contact sites and the leakage of fluid past the contact surfaces. In its broadest sense, this is achieved according to the invention when the connector jack has at least on flat disk-shaped means containing electrically conductive material, with one or more contact surfaces arranged at the perimeter of a central hole through said disk-shaped means and adapted to come into contact with the corresponding contact surfaces on the contact pin, which has a diameter slightly exceeding the diameter of the central hole, and a layer of insulating, elastic material on both sides of the electrically conductive material, at least in the area of the contact surfaces interacting with the contact pin, said disk-shaped means being arranged to be elastically deformed by the contact pin when the pin is inserted into the central hole such that the electrically conductive material's contact surfaces and the insulating material are pressed against the corresponding contact surfaces on the contact pin while the contact surfaces thereby, at the same time, are protectively sealed by the insulating material. In one preferred embodiment of the invention, the connector jack comprises a plurality of disk-shaped lamellae of electrically conductive material having layers of electrically insulating material on both sides thereof, the contact surfaces of the lamellae being formed by edges of the central hole of the lamellae. According to an alternative embodiment of the invention, the connector jack has one or more flat disks made of an elastic, electrically insulating material, in each of which is embedded one or more layers of means (40,44), mainly in the plane of said disk, made of electrically conductive material, each disk also having a hole matching the peripheral configuration of the contact pin, whereby hole edges of the means form contact surfaces arranged to press against the contact surfaces on the contact pin when the contact pin is inserted into the hole of the disk or disks, the elastic insulating material conveying protective sealing of the contact surfaces. Additional features and advantages of the connector according to the invention will be described below in greater detail in the following patent claims, referring to attached drawings in which: FIG. 1 is a lateral view of a pacemaker with a schematically indicated connector for sealed contact with the corresponding contact pin surfaces on a bipolar electrode cable; FIG. 2 is a schematic, axial, longitudinal, sectional view of a connector jack according to a first embodiment of the invention; FIG. 3 is an end view of the connector in FIG. 2; FIG. 4 is a view, corresponding to FIG. 2, but shows the deformation of the electrically conductive means and the sealing around the contact surfaces against a contact pin, inserted into the connector, on the proximal end of the electrode cable; FIG. 5 is a perspective view of an alternative embodiment of a connector jack according to the invention; and FIG. 6 is a view, like FIG. 5, of an additional embodiment of the invention. FIG. 1 schematically depicts a pacemaker 10 with an electronics section 12 and a connection section 14 for a bipolar electrode cable 16. Two connector jacks 18 according to the invention are mounted onto or molded into the connection section 14, each jack to admit a polar contact surface on the proximal end of the electrode cable 16 which is insertable into and affixable in the connection section 14. As FIG. 2 shows, each connector 18 can contain a plurality of electrically conductive lamellae 20 which are kept separated by elastic, electrically insulating disks 22 made of e.g. silicone. The disks 20, 22 are preferably laminated together into a cohesive multilayer "sandwich" which can be kept in place by a surrounding housing 24 made of an electrically conductive material. The electrically conductive multilayered disks 20 and insulation disks 22 in the multi layer "sandwich" have a central hole 26 whose diameter is somewhat smaller than the external diameter of the electrode contact surface which is to be brought into contact with the multi layer disks 20 for a purpose to be described in greater detail below. The inner edge surfaces 28 of the multi layer disks 20 are exposed in the hole 26 and can be displaced radially somewhat from the inner periphery 22 of the insulating disks in order to create distinct contact surfaces inside the connector jack 18. The shell 24 consists of two U-shaped housing halves 30, 32, one half telescoping into the other, whereby the inner housing half 30 can be force-fitted into the outer half 32 during simultaneous clamping of the multi layer "sandwich". The radial, external contact surfaces 34 of the conductive lamellae 20 are, like the inner edge areas 28, exposed so they can distinctly contact the conductive housing half 30, which by means of conductors 31 suggested in FIG. 1, connect the connector jack to the electronics unit 12. The bottom sections 30a and 32a of the housing halves 30, 32, which form the end walls of the connector 18, have an opening 36 which is coaxial to the central hole 26 and which has a diameter somewhat greater than the diameter of the hole 26, so the multi layer "sandwich" acquires a radial, inward projecting part, in relation to the housing's openings 36, which can be easily deformed by bending, and are tensioned when a contact pin 27 on the proximal end of the electrode cable 16 is inserted into the hole 26, as shown in FIG. 4. When the diameter of the contact pin 37 is larger than the diameter of the hole 26 in the connector jack 18, bending deformation of the radial inner edge areas of the conductive lamellae 20 occurs, causing them to be tensioned against the contact surface of the contact pin 37 and the opposite, internal part of the conductive housing 30 in order to enhance contact pressure between the lamellae 20, and thus, signal transmission between the electrode cable 16 and the electronics section 12. With the proposed connector 18 according to the invention, automatic forced contact is achieved between the electrode pin 37 and the connector jack 18, as well as intimate sealing at the contact sites, thanks to insulating material 22, integrated into the lamellae 20, which are sealingly pressed by the said deformation against the contact pin's 37 contact surfaces, thereby preventing the development of junction corrosion at the contact surfaces and leakage of body fluid onto and past contact surfaces. The conductive lamellae 20 can be devised in many different ways within the scope of the invention. In addition to the circular disk shape shown in FIGS. 2-4, the lamellae can have another outer, perimeter configuration. As shown in FIGS. 5 and 6, the connector jack can alternately be made of one or more disks 38 of an elastic, insulating material in each of which is embedded one or more layers, mainly on the plane of the disk, of means made of electrically conductive material. The electrically conductive means shown in FIG. 5 consist of a plurality of radially arranged metal rods 40 embedded in an insulating material 42. In FIG. 6, the electrically conductive means consist of a plurality of metal bands or strips 44, arranged in two axially separate layers and also embedded in an electrically insulating, elastic material 42, e.g. silicone. The electrically conductive means can also have another configuration appropriate to the purpose, e.g. a mesh structure not shown in the drawing. Even in the embodiments according to FIGS. 5 and 6, the exposed radially arranged inner and outer ends of the electrically conductive means 40, 44 are devised to press, when a contact pin is inserted, against the corresponding contact surfaces of the pin and a surrounding contact section which is connected to the electronics section 12 by a conductor, providing simultaneous, intimate sealing of the contact sites. The multi layer "sandwich" 20, 22 and the disks 38 can be provided with recesses or holes 46 and 48 respectively to facilitate compression and deformation and, accordingly, match the shape of these parts to the electrode contact pin 37 when the pin is inserted into the connector jack. Separate means, not shown in FIG. 1, can be arranged in the connection section 14 to keep the electrode cable 16 from being pulled out once contact has been established between the respective contact pin parts and the connector jack 18.

Claims: An electrical connector jack, especially for contact with a contact pin (37) on the proximal end of an electrode cable (16), connectable to an implantable heart stimulator (10), such as a pacemaker or defibrillator, characterized in that the connector jack (18) has at least one flat disk-shaped means (20) containing electrically conductive material with one or more contact surfaces (28), arranged at the perimeter of a central hole (26) through said disk-shaped means and adapted to come into contact with the corresponding contact surfaces on the contact pin (37), which has a diameter slightly exceeding the diameter of the central hole (26), and a layer (22) of insulating, elastic material on both sides of the electrically conductive material (20), at least in the area of the contact surfaces interacting with the contact pin (37), said disk-shaped means (20) being arranged to be elastically deformed by the contact pin (37) when the pin is inserted into the central hole (26) such that the electrically conductive material's contact surfaces (28) and the insulating material (22) are pressed against the corresponding contact surfaces on the contact pin while the contact surfaces thereby, at the same time, are protectively sealed by the insulating material. A connector jack according to Claim 1, characterized in that it comprises a plurality of disk-shaped lamellae (20) of electrically conductive material having layers (22) of electrically insulating material on both sides thereof, the contact surfaces (28) of the lamellae (20) being formed by edges of the central hole (26) of the lamellae (20). A connector jack according to Claim 2, characterized in that the radially outer edges of the lamellae (20) are arranged to press conductively against a retention means (24), made of electrically conductive material, housing the lamellae (20) and the layers (22) of insulating material. A connector jack according to Claim 3, characterized in that the retention means (24) contains two telescopically slidable, mainly U-shaped shell halves (30,32), whose bottom sections (30a,32a) are arranged to press against the respective sides of the external layer of insulation (22), whereby at least one of the bottom sections (30a,32a) has an opening coaxial to the central hole (26) of the lamellae (20) to admit the electrode contact pin (37) into the contact area of the latter. A connector jack according to any of Claims 2 to 4, characterized in that the elastically insulating material (22) has notches (46) to facilitate deformation of the lamellae (20). A connector jack according to any of Claims 2 to 5, characterized in that the lamellae, at least in the area of the central hole (26), have slots or notches to facilitate deformation of the lamellae. An electrical connector jack, especially for contacts with a contact pin (37) on the proximal end of an electrode cable (16) which can be connected to an implantable heart stimulator, such as a pacemaker or defibrillator, characterized in that the connector (18) has one or more flat disks (38) made of an elastic, electrically insulating material (42), in each of which is embedded one or more layers of means (40,44), mainly in the plane of said disk, made of electrically conductive material, each disk (38) also having a hole matching the peripheral configuration of the contact pin, whereby the edges of said means in said hole form contact surfaces arranged to press against the contact surfaces on the contact pin when the contact pin is inserted into the hole of the disk or disks, the elastic insulating material conveying protective sealing of the contact surfaces. A connector jack according to Claim 7, characterized in that the electrically conductive means is in the form of a plurality of metal rods (40), extending mainly radially to the contact pin which is to be inserted into the hole in each disk. A connector jack according to Claim 7, characterized in that the electrically conductive means are in the form of a plurality of metal strips (44), lying mainly on the plane of the disk (38), and extending mainly radially to the contact pin to be inserted into the hole in each disk. A connector jack according to any of Claims 7 to 9, characterized in that radially outer edges of the electrically conductive means are arranged to press against a means, made of an electrically conductive material, to conductively retaining the disk or disks. A connector jack according to Claim 10, characterized in that the retaining means consists of two telescopically and slidingly arranged, mainly U-shaped, shell halves whose bottom sections are arranged to press against the respective outer sides of the disk (38) or disks, the bottom sections having openings, coaxial to each other and the hole in the disk(s), with a diameter larger than the hole in the disk(s) to permit elastic deformation of the contact area on the electrically conductive means next to the contact pin when the pin is inserted. A connector jack according to any of Claims 7 to 11, characterized in that the elastic, insulating material (42) has notches to facilitate deformation of the disk (38) or disks.

Inventors: JARL PER-ERIK, JARL,PER-ERIK
Applicants: PACESETTER AB
Application year: 1996
Main classification: H01R13
IPC codes: H01R13, H01R4, A61B5, A61N1