Abstract:
A sealed cover and plastic cartridge combination for electrical connections providing sealing, strain relief, mechanical retention, electrical insulation and flex relief similar to that achieved using an over-molded design includes a plastic cartridge of integral construction or composed of two or more parts, in either case housing one or more contacts of the connections.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATION 
       [0001]    The present patent application is a continuation-in-part of U.S. patent application Ser. No. 11/053,579, which claims the benefit under 35 USC 119 and 120 of the filing date and priority of provisional U.S. patent application Ser. No. 60/543,426, filed 9 Feb. 2004. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to an apparatus and method for protecting the electrical connections within an electrical cable. More specifically, the present invention is a cable assembly comprised of a plug and a receptacle. Both the plug and the receptacle are each comprised of a sealing cover and a plurality of cartridges contained therein. The cartridges are adapted to retain one or more electrical contacts such that, when the plug is connected with the receptacle, the contacts place the plug into electrical communication with the receptacle. 
       Background of the Invention-Description of the Prior Art 
       [0003]    Electronic cables remain ubiquitous as a necessity for powering and/or assisting in the passage of electronic data or information. At their core, many electronic cables are comprised of one or more wires electrically communicated with at least one contact. The contact is usually receivable by a corresponding port or receptacle. In many instances, it is imperative that the contact be received by the receptacle without interference such that the electrical flow along the connection remains uninterrupted. To this end, the contact should be adapted to be received by the receptacle so as to maintain the electrical connection without allowing environmental elements to interfere with or even break this connection. 
         [0004]    Over molding is one known solution used in the art for protecting electrical cables. The term “molding” is used to refer to an electrical connector having a molded connector body housing the contacts, which are connected to one or more electrical wires. Referring to  FIGS. 6 ,  7 , and  8 , a typical over molded electrical cable assembly is illustrated as comprising one or more wire strands  106 , at least one contact  102 , a pre-mold  110 , and an over mold  112 . The contact  102  is illustrated as a rod-like element, preferably comprised of a electrically conductive material. The contact  102  is rounded at one end forming a male end of the cable that is adapted to electrically communicate with a corresponding female port or receptacle (not illustrated). 
         [0005]    A pair of receivers  104  extend from the opposing end of the contact. The receivers  104  are aligned to receive one or more wire strands  106  extending from a jacketed portion  107  of an insulated wire  108 . The receivers  104  are usually crimped or soldered to wire strands  106  so as to mechanically retain the wire strands  106  and effectuate good electrical conductivity between the wire strands  106  and the receivers  104 . Ultimately, the connection between the receivers  104  and the wire strands  106  places the contact  102  into electrical communication with the wires. 
         [0006]    Once the wire strands  106  are coupled to the receivers  104 , the wire and contact sub assembly goes through a molding process known as a “pre-mold,” illustrated by reference numeral  110 . More specifically, a pre-mold is typically a pre-formed sleeve comprised of a rigid material, usually a thermoplastic such as nylon, to encapsulate the wire  108  and receivers  104 . Referring to  FIG. 7 , the pre-mold  110  sleeve is sized to move axially along the insulated wire  108  into position over the wire/receivers intersection. The premold  110  is typically of a sufficient size such that it may be slid into place with relative ease, but is also of a sufficient elasticity to frictionally hold the wire strands  106  and receivers  104  there-within. Accordingly, the premold  110  provides both mechanical reinforcement and electrical insulation for the contacts and wires. 
         [0007]    Once the premold  110  is in place, an over mold  112  is added as an additional layer. An over mold  112  is typically comprised of a flexible material, such as vinyl nitrile or PVC, that is pre-fabricated to fit over the pre-mold  110  and wire assembly. Much like the pre-mold layer  110 , the over mold  112  sleeve is sized to move axially along the insulated wire  108  into position over the pre-mold  110 . The over mold  112  is typically of a sufficient size such that it may be slid into place with relative ease, but is also of a sufficient elasticity to frictionally hold the pre-mold  110  there-within. This additional layer adds further encapsulation, flex and strain relief, tamper resistance, and, in some cases, resistance to fluids. The over mold  112  may further include a flexible stress/strained relief member  114  integrally molded therein. The flexible stress/strained relief member  114  provides flexible relief with respect to the electrical connection maintained by receivers  104  being coupled to wire strands  106 . 
         [0008]    Overmolding is a cost effective technology for high volume production. For low and medium volume production, however, it is less attractive for a plurality of reasons. First, the cables cannot be easily reworked. In other words, once the premold  110  and over mold  112  are put into place, the wires cannot easily be disconnected to the contact and rewired to a separate contact. Second, over molding requires mold tools and mold presses. To this end, the manufacturer would have to incur significant start up costs in obtaining the proper manufacturing equipment. These costs can be prohibitive for smaller volume cable assemblies because it would require a longer amount of time to recoup these start up costs. Third, over molded cables have to be factory assembled. This can also add significant costs and delays to production of the cable. 
         [0009]    Based on the foregoing, there is a pressing need within the field of electrical, communications and other cables or transmission systems to provide an economically efficient, safe and highly moisture resistant coupling device that will permit the user to easily and quickly connect and disconnect electrical, communication or other lines or devices a plurality of times without compromising system integrity or high moisture resistance with each subsequent reconnection. Furthermore, there is a pressing need within the art for an electrical communication cable that may be easily manufactured with minimal start up costs so as to benefit small and medium volume producers. Finally, there is a pressing need within the art for an electrical communication cable that is able to seal electrical contacts for environmental conditions while allowing an operator to rework the contacts where necessary. 
         [0010]    The present invention, as discussed herein, addresses the foregoing needs. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention relates to an apparatus and method for protecting the electrical connections within an electrical cable. More specifically, the present invention relates to a cable assembly comprised of a plug and receptacle wherein the receptacle is adapted to mate with and be secured to the plug. 
         [0012]    Both the plug and receptacle are each comprised of independent sealing covers containing a plurality of plastic cartridges and electrical contacts. The sealing cover of the plug is comprised of an annularly shaped wall forming a lumen that passes between an open distal end and an open proximal end of the plug. The open distal end of the plug&#39;s sealing cover is adapted to receive a plurality of electrical wires, and the open proximal end of the sealing cover is adapted to threadingly or frictionally engage the receptacle and display the electrical contacts. The plug&#39;s lumen is sized to contain a first cartridge chamber sized to hold a plurality of first cartridge blocks therein such that the electrical contacts contained within the first cartridge blocks are accessible from both the distal and proximal ends of the sealing cover. Preferably, the cartridge chamber is adapted to receive and frictionally hold four cartridge blocks wherein the cartridges blocks may be bonded together as one unit or separated into four distinct units. 
         [0013]    The sealing cover of the receptacle is similarly comprised of an annularly shaped wall forming a lumen passing between an open distal end and an open proximal end of the receptacle. The open distal end of the receptacle&#39;s sealing cover is adapted to receive a plurality of electrical wires, and the open proximal end of the sealing cover is adapted to receive the plug by threading or frictional engagement. The receptacle&#39;s lumen is sized to contain a second cartridge chamber that holds a plurality of second cartridge blocks therein such that the electrical contacts contained within the first cartridge blocks are accessible from both the distal and proximal ends of the sealing cover. Preferably, the cartridge chamber receives and frictionally holds four cartridge blocks wherein the cartridge blocks may be bonded together as one unit or separable into four discrete units. Most preferably, the plurality of the second cartridge blocks are adapted to mate with the plurality of first cartridge blocks through the open proximal ends of the two sealing covers. 
         [0014]    Both the first and second cartridge blocks are of a configuration such that they may be installed within each respective cartridge chamber and interconnected so as to encapsulate the first and second contacts therein. In particular, each cartridge block is polyhedronally shaped with an open distal end and an open proximal end and a lumen passing therebetween. The open proximal end is comprised of a cutaway portion of each cartridge block wherein approximately half of the height of the cartridge block is removed providing a channel in the remaining portion. Preferably, the cartridge blocks, when installed into the plug and receptacle, have opposing cutaway portions exposed at the proximal end of each sealing cover such that, when the plug is mated with the receptacle, the channel of the first cartridge block overlaps the cutaway portion of the second cartridge block and vice versa. Accordingly, when the plug is mated with the receptacle, the two the cartridge blocks overlap to form a single housing. 
         [0015]    Contained within each cartridge block is an electrical contact. The electrical contact is sized to fit within the lumen of each cartridge block such that the lumen walls frictionally secure the contact therein. The contacts may also be bonded to the lumen walls so as to further secure the contact within the cartridge blocks. A first end of the contact is accessible through the open distal end of the cartridge block. In a preferred embodiment, the first end of the contact is sized to completely fill the lumen at the distal end of the cartridge block such that the first end of the contact is flush with the distal end of the cartridge block. A second end of the contact is sized to fill the void created in the cut away portion of the proximal end of the cartridge block. Most preferably, the second end of the contact is not within the remaining channel of the proximal end of the cartridge block. Rather, the second end of the contact further defines the remaining channel at the proximal end of the cartridge chamber. Accordingly, the proximal end of each cartridge block is comprised of a contact within the cutaway portion and a channel adjacent to the contact. 
         [0016]    The channel created within each cartridge block is adapted to receive the contact of an opposing cartridge block. As noted above, the cartridge blocks of the plug and receptacle have opposing cutaway portions. To this end, they also have opposing contacts to fill the cutaway portions and opposing channels juxtaposed to the contacts. In the most preferred embodiment, each channel is adapted to receive the opposing contact such that, when the plug and receptacle are mated, the channels of each cartridge block receive the opposing contact and overlap with the cutaway portion of the opposing cartridge block. In this configuration, the two electrical contacts of the two opposing cartridge blocks are placed into electrical communication with each other and the two opposing cartridge blocks overlap so as to completely encapsulate the contacts therein. 
         [0017]    As noted above, a plurality of cartridge blocks and contacts may be contained with each of the plug and receptacle. Preferably, each of the plug and receptacle are comprised of four cartridge housings wherein each cartridge housing contains one electrical contact. The blocks are installed within the cartridge chamber of each of the plug and receptacle such that the distal end of the cartridge blocks are proximate to the distal end of the sealing cover and the proximal end of the cartridge blocks are proximate to the proximal end of the sealing cover. The four housings are positioned within the lumen of the plug such that the proximal end of each cartridge block interconnects with the proximal end of a similarly placed opposing cartridge block of the receptacle. Accordingly, when the plug and receptacle are mated, each of the four cartridge housings of the plug are independently interconnected so as to overlap with corresponding cartridge housings of the receptacle. Moreover, when the plug and receptacle are mated, the contacts of each of the first cartridge blocks of the plug are placed into electrical communication with the contacts of the corresponding second cartridge blocks of the receptacle 
         [0018]    The contacts of both of the plug and the receptacle are independently in electrical communication with a plurality of electrical wires. The wires extend from outside of the respective sealing covers and through the respective distal openings of the sealing covers into each respective cartridge chamber. The wires may be placed into electrical communication with the first end of each contact by way of the open distal end of each cartridge block. The wires may be secured to the contact by any standard method of securing an electrical contact to a wire that is known in the art. In a preferred embodiment, there are four wires extending into each sealing cover wherein each wire is placed into electrical communication with one contact. 
         [0019]    The electrical wires may be further secured within the sealing covers of the plug and receptacle by a wiring harness. The wiring harness may be frictionally or threadingly securable within the distal end of the sealing cover with one or more holes adapted to secure the electrical wires to the harness. In the most preferred embodiment, the wiring harness contains at least four holes wherein each hole is adapted to secure one wire to the sealing cover and stabilize the wire so as to prevent the wire from inadvertently dislodging from electrical communication with the contact. 
         [0020]    Based on the foregoing, one object of the present invention is to provide a plurality of electrical connections within a plug and receptacle system wherein the electrical connections are completely insulated from environmental conditions. 
         [0021]    It is a further object of the present invention to provide a plug and receptacle system wherein, when the plug and receptacle mate, at least two distinct housings encapsulate the electrical connections therein. 
         [0022]    It is a further object of the present invention to provide a plug and receptacle system wherein, when the plug and receptacle mate, the electrical connections contained there are encapsulated by overlapping cartridge blocks and the sealing covers of the plug and receptacle. 
         [0023]    It is another object of the present invention to provide electrical contacts within a plug and receptacle that may be easily replaced. 
         [0024]    It is a further object of the present invention to provide a plurality of electrical contacts within a plug and receptacle that may be replaced individually or as an entire unit. 
         [0025]    Additional object and advantages that are apparent to one of ordinary skill in the art are also included as understood from the specification provided herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]      FIG. 1  is a schematic representation of an electrical cable according to the present invention. 
           [0027]      FIG. 2  is an exploded isometric view illustrating a sealed cover and plastic cartridge package in accordance with the preferred embodiment of the invention. 
           [0028]      FIG. 3  is a broken isometric view of the interior of a portion of a sealed cover of a receptacle of the invention. 
           [0029]      FIG. 4  is a broken isometric view of the interior of a sealed cover part of the invention together with a plastic cartridge shown therein. 
           [0030]      FIG. 5  is a front elevation of the cartridge illustrated in  FIG. 4 . 
           [0031]      FIG. 6  is a schematic representation of a prior art electrical cable wherein a plurality of electrical wires are connected to a contact. 
           [0032]      FIG. 7  is a schematic representation of a prior art electrical cable wherein a pre-mold covers the wire/contact connection. 
           [0033]      FIG. 8  is a schematic representation of a prior art electrical cable with an over-mold covering the pre-mold and contact/wire connection. 
           [0034]      FIG. 9  is a broken isometric view of the interior of a portion of a sealed cover of a plug of the invention. 
           [0035]      FIG. 10   a  and  10   b  are front and rear views, respectively, of a block of four cartridges. 
           [0036]      FIG. 11  is a broken isometric view of the interior of a portion of a sealed cover of a receptacle of the invention wherein one-half of a block of cartridges is contained therein. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0037]    The present invention relates to an apparatus and method for protecting the electrical connections within an electrical cable. More specifically, the present invention is a cable assembly comprised of a plug and receptacle. Both the plug and receptacle are comprised of a sealing cover sized to hold a plurality of plastic cartridges. The plastic cartridges are adapted to retain one or more electrical contacts therein such that the plug is placed into electrical communication with the receptacle when the two are interconnected. To this end, this present apparatus addresses and eliminates the aforementioned problems associated with over-molded electrical connectors. 
         [0038]    Referring to  FIGS. 1 and 2 , a cable assembly  1  is illustrated. More specifically, the cable assembly  1  is comprised of a plug  2  and a receptacle  4 . As illustrated, both the plug  2  and the receptacle  4  are comprised of independent sealing covers  14  and a plurality of plastic cartridges  16 . Each plastic cartridge  16  contains at least one electrical contact  6  wherein each first electrical contact of a plug  2  is adapted to be placed in electrical communication with a corresponding second electrical contact of a receptacle  4 . The corresponding contacts  6  when connected, thereby, complete an electrical circuit between the plug and the receptacle, as discussed further herein. 
         [0039]    Referring to  FIGS. 3 and 9 , an annularly shaped sealed cover of the receptacle  4  and plug  2  are illustrated wherein  FIG. 3  illustrates the receptacle  4  and  FIG. 9  illustrates the plug  2 . The sealed covers of both the receptacle and plug  14   a ,  14   b  are annularly shaped so as to form annular exterior surfaces  20   a  and  20   b , respectively, and an interior surfaces  18   a  and  18   b , respectively. The sealed cover  14   a  of the receptacle  4  is substantially cylindrical with hollow cavity formed from the interior surface  18   a  wherein the hollow cavity passes from an open proximal end  8  of the receptacle to an open distal end  9 . Similarly, the sealed cover  14   b  of the plug  2  is also substantially cylindrical with hollow cavity formed from the interior surface  18   b  wherein the hollow cavity passes from an open proximal end  24  of the receptacle to an open distal end  26 . 
         [0040]    The sealed covers  14   a    14   b  are desirably comprised of a soft, flexible, rubber-based material formed from a rubber molding technology that is known in the art. In one embodiment, the sealed covers  14   a  and  14   b  are made from a silicone or silicone based rubber. In an alternative embodiment, the sealed covers may also be comprised of a hydrocarbon-based polymeric rubber. For example, the polymeric material may comprised of vinyl nitrile or a vinyl nitrile based material. To this end, any of the forgoing materials, or combinations of the forgoing materials, may be used in the present invention so long as they are consistent with the specifications provided herein. The thickness of the sealed covers  14   a ,  14   b  and the hardness of the material used are important for optimal operation. Particularly, the hardness and thickness of the sealed covers  14   a ,  14   b  are preferably such that the sealing covers are ridge yet able to expand to fit over a plurality of plastic cartridge blocks  16  or block units  12 . Accordingly, the thickness and hardness of the material is balanced to ensure that sealed covers  14   a ,  14   b  can be expanded without tearing or stretching on the one hand, but the material must be firm enough to properly cover the plastic cartridge blocks  16  and remain in place. 
         [0041]    The proximal end  24  of the plug&#39;s sealed cover  14   b  is preferably sized so as to concentrically fit over the proximal end  8  of the receptacle&#39;s sealed cover  14   a  such that the receptacle  4  may be lockingly engaged by the plug  2 . In one embodiment, a plurality of ridges  10  are present on the outer surface  20   a  of the receptacle  4 , preferably at or near the proximal end  8  of the receptacle  4 . The ridges  10  are adapted to frictionally engage a plurality of corresponding ridges  20  in an aspect of the interior surface  18   b  of the plug  2 , preferably, at or near the proximal end  24  of the plug  2 . Specifically, the ridges  20  may be on an interior surface of an annular collar  28  of the plug  2  wherein the collar  28  is integrally formed with the proximal end  8  of the plug  2  and has a diameter slightly larger than the body of the plug  2 . Preferably, the collar  28  is sized so as to fit over the proximal end  8  of the receptacle  4  such that the ridges  10 , of the receptacle and plug, respectively, can frictionally engaged one another. Accordingly, upon mating the plug  2  with the receptacle  4  the frictional engagement between the ridges  10 ,  20  functions to secure the plug to the receptacle and isolate the electrical connection from environmental conditions. 
         [0042]    In an alternative embodiment, the plurality of ridges  10 ,  20  represent threads. The threads  10  of the receptacle  4  are adapted to threadingly engaged the corresponding threads  20  of the collar  28 . In this embodiment, the collar  28  may be adapted to rotate independently of the of the plug  2  and about the plug&#39;s longitudinal axis. The collar  28 , therefore, may be coupled to the plug  2  by way of a bearing or other similar device to allow for rotation of the collar  28  without affecting the body of the plug  2 . Upon mating the plug  2  with the receptacle  4 , the collar  28  threadingly engages the threads  10  proximal end  8  of the receptacle  4  by independently rotating about the longitudinal axis of the plug  2  and, thereby, lockingly engaging the plug to the receptacle. 
         [0043]    In a further embodiment, either in conjunction with or in place of the previous embodiments, the proximal end  24  of the plug  2  may snap fit into the proximal end  8  of the receptacle  4 . More specifically, as illustrated in  FIG. 3 , the proximal end  8  of the receptacle may contain a recess  30  about the exterior cover  20   a  of the receptacle wherein the recess  30  is preferably distal to the ridges/threads  10 . The recess  30  corresponds with a large, annular ridge  32  extending about the proximal end  24  of the plug on the interior surface  18   b . Preferably, the ridge  32  extends along the interior surface of collar  28  in proximally from the ridges/threads  20 . As illustrated in  FIG. 4 , when the collar  28  of the plug  2  engages the proximal end  8  of the receptacle  4  the plug&#39;s larger ridge  32  fits into the receptacle&#39;s recess  30 , thereby, further frictionally securing the plug to the receptacle. 
         [0044]    Referring to  FIGS. 3 and 9 , spaced between the proximal end and distal end of both the sealing covers of the receptacle and plug are cartridge retaining chambers  34   a ,  34   b . Both cartridge retaining chambers  34   a  and  34   b  are formed from the interior sides  18   a  and  18   b  of the receptacle and plug, respectively, and are sized to receive and secure a plurality of electrical contact containing cartridge blocks  16 . In both the plug and the receptacle, chambers  34   b  and  34   a  may be rectangularly shaped with a first open end and a second open end. In the plug, the first open end  36   b  leads to the proximal end  24  of the plug, while the second open end  38   b  leads to the distal end  26  of the plug. Similarly, in the receptacle, the first open end  36   a  leads to the proximal end  8  of the receptacle, while the second open end  38   a  leads to the distal end  9  of the receptacle. Referring to  FIG. 9 , the perimeter of second open end  38   b  of the plug  2  is formed by a retaining wall  40   b  such that the size of the second open end  38   b  is smaller than the size of both the first open end  36   b  and the cartridge retaining chamber  34   b . The retaining wall  40   b , thereby, provides a rear stopping position for the cartridge blocks  16  inserted into the plug through its proximal end  24 , as illustrated in  FIGS. 4 and 11 . The retaining wall  40   b , however, is sized to leave an opening at the distal end of the retaining chamber  34   b  such that each of the cartridge blocks  16  are accessible through the distal end  26  of the plug. Similarly, referring to  FIG. 3 , the perimeter of second open end  38   a  of the receptacle  4  is formed by a retaining wall  40   a  such that the size of the second open end  38   a  is smaller than the size of both the first open end  36   a  and the cartridge retaining chamber  38   b . To this end, the perimeter of the retaining wall  40   a  provides a rear stopping position for the cartridge blocks  16  within the receptacle. The retaining wall  40   a , however, is sized to leave an opening at the distal end of the retaining chamber  34   a  such that each of the cartridge blocks  16  within the receptacle  4  are accessible through the distal end of the receptacle. 
         [0045]    Referring to  FIGS. 2 ,  10   a  and  10   b , a plurality of cartridge blocks  16  of the present invention are illustrated as each comprising a housing member  56  and an electrical contact  58  within the housing. In one embodiment, the housing  56  of each cartridge block  16  may be comprised of nylon or polycarbonate polymer that is molded into a polyhedronally shape, preferably in the form of a hexahedron or similar structure, with a hollow cavity or lumen contained therein. The hollow cavity passes from a proximal end  42  of the housing  56  to the distal end  44  of the housing so as to create an opening at each proximal and distal end. The opening in the distal end  44  of housing  56  is substantially squared in shape so as to mimic the shape of the housing. However, the present invention is not limited to this embodiment, and the opening at the distal end  44  may be of any shape so long as the electrical contact secured within the housing  56  is accessible therethrough. 
         [0046]    The hollow cavity also leads an opening at the proximal end  42  of the housing  56 . More specifically, in one embodiment the opening may be similar to that of the distal end  44  of the housing  56  in that it mimics the shape of the housing. Preferably, however, a portion of the proximal end  42  of the housing  56  is removed or cut away. Referring to  FIG. 10A , a plurality of cartridge blocks are illustrated wherein the top half portion of the proximal end  42  of the housing is removed such that the lower half of the proximal end  42  forms a substantially U-shaped channel  60 . This configuration creates an open channel  60  at the lower half of the proximal end  42  and an open space or void at the upper half. As illustrated in  FIG. 1 , however, the housing  56  is not limited to this configuration and may be in an opposing or reversed configuration wherein the lower half portion of the cartridge block may be removed creating a void and leaving a channel  60  in the upper half of the housing. To this end, these opposing configurations of cartridge blocks may be arranged within a plug and receptacle such that the cut away portion of a first cartridge block receives the channel portion of an opposing second cartridge block and vice versa. 
         [0047]    The hollow cavity of the housing  56  is adapted to receive and secure an electrical contact  58  therein. More specifically, the contact is shaped so as to substantially mimic the interior cavity of the housing  56 , especially with respect to the distal end of the housing  56 . In a preferred embodiment, the contact  58  is formed such that it is polyhedronally shaped, preferably in the form of a hexahedron or similar structure with a distal end and a proximal end. The distal end of the contact  58  is illustrated in  FIG. 10B  as substantially squared in shape so as to mimic the hollowed cavity of the housing wherein the distal end of the contact is accessible through the distal end  44  of the housing  56 . To this end, the distal end of the contact may be frictionally secured to the interior walls of the housing  56  or bonded thereto with a glue or similar bonding agent. 
         [0048]    The proximal end of the contact  58 , as illustrated in  FIG. 10A , is adapted to fill void created in the cut away portion of the proximal end  42  of the housing  56  and further define the channel  60 . More specifically, the perimeter of the proximal end of the contact  58  is smaller than that of the distal end. Preferably, the perimeter of the proximal end of the contact is approximately half that of the distal end such that a portion the proximal end of the contact  58  appears removed or cut away. Most preferably, the proximal end of the contact  58  is sized to extend into and substantially fill the void created in the cut away portion of the housing  56 . However, the proximal end of the contact  58  does not interfere with the channel  60  of the housing  58 ; rather, the proximal end of the contact  58  extends parallel to the channel  60  so as to provide a channel boundary. As described further herein, in this configuration, the channel  60  and contact  58  cooperate in receiving a contact from an opposing cartridge block wherein the opposing contact is received into the channel  60  and placed into electrical communication with contact  58 . 
         [0049]    The plurality of foregoing cartridge blocks  16  may be individually inserted into the chambers  34   a  and  34   b  of the receptacle and plug such that the blocks  16  are held in place by the frictional engagement therebetween and by the interior walls of the cartridge chambers. More specifically, the chambers  34   a  and  34   b  are sized to fit a plurality of cartridges such that the contact portion of each cartridge is exposed at or about the proximal ends of the plug and receptacle. Most preferably, as illustrated in  FIGS. 1 and 2 , the chambers  34   a  and  34   b  are each sized to fit four cartridges blocks  16 . The area of each chamber  34   a  and  34   b  is, therefore, approximately the same, or slightly smaller, as the area of the four cartridge blocks  16  such that the chamber  34   a  and  34   b  may frictionally secure the cartridge blocks  16  therein. The chambers  34   a  and  34   b  may be further shaped so as to secure the cartridges by using one or more alignment features wherein the alignment features provide mechanical strength to secure the sealed cover to the plastic cartridge blocks  16 . Such alignment features may include, but are not limited to a plurality of recesses  37  spaced about the periphery of the chambers  34   a  and  34   b . Each recess may correspond with a similarly sized ridge (not illustrated) or spring on the body of the cartridges  16 . In other words, features molded into the chambers  34   a  and  34   b  of the sealed covers  14   a  and  14   b  match features on the plastic cartridge blocks  12 . This alignment enables the cartridge blocks  16  to be secured within the chambers  34   a  and  34   b  and prevents the parts from separating under normal use. 
         [0050]    In a preferred embodiment, the plurality of blocks may be bonded together prior to installation so as to form a singular block unit  12 . This singular block unit  12  facilitates aligning the cartridge blocks  16  with the alignment features of the cartridge chamber and has the added advantage of facilitating installation and/or replacement of the electrical connections within the cable assembly. Accordingly, one can easily install, remove and/or replace the contact of a plug or receptacle by the removal and/or installation of the singular block unit  12 . Referring again to  FIGS. 10   a  and  10   b , and in accordance with the above, four cartridge blocks  16  may be bonded together so as to form a single block unit  12  wherein a first block unit  12  may received within chamber  34   a  of the receptacle  4  and an opposing second block unit  12  may be received within chamber  34   b  of plug  2 . Preferably, referring to  FIG. 1 , the block units are installed into the plug and receptacle such that similarly placed the cartridge blocks are positioned in opposition to each other so as to facilitate the electrical connectivity between the contacts of the plug  2  and the receptacle  4 . For example, as illustrated in  FIG. 1 , the block unit  12  of a receptacle  4  may be oriented such that the channel  60  at the proximal end  42  of each housing  56  is beneath the contact  58 . Conversely, the block unit  12  of the plug  2  is oriented such that the channel  60  at the proximal end  42  of each housing  56  is above the contact  58  extending into the void of the housing  56 . Accordingly, when the plug and the receptacle mate, each respective contact is received into the channel of the opposing housing. The two opposing contacts are, thereby, placed into electrical communication with each other and insulated from environmental conditions by way of the overlapping and opposing housings  56 . 
         [0051]    The structure of the cartridge blocks and the contacts above are not limiting to the structure of the invention. Rather, the mold of the cartridge blocks and the contacts therein may be in any form known in the art for establishing electrically communication. In any of these forms, however, it is preferred that the connectivity be contained completely within the interlocking blocks such, once interconnected, the blocks shield the contacts from environmental conditions. 
         [0052]    Each contact  58  of each cartridge block is also in electrical communication with one or more wires extending into the sealing cover by way of its distal end. Preferably, the contact is in electrical communication with the wiring by way of the opening in the distal end of the housing  56 . Referring to  FIGS. 4 and 11 , in one embodiment, the wiring extends into and through the distal end of the sealing covers  14   b ,  14   a  in each of the plug  2  and the receptacle  4  such that it is coupled to the contacts  58  at the distal end of the cartridge block housing  56 . The wiring may be coupled to the contacts by any method understood in the art to secure an electrical wire to and electrical contact. In one embodiment, the wiring may be soldered to the contact. In another embodiment, the wiring may be crimped to an extension of the contact. The wiring may also be secured to the contact by any similar method known in the art for maintaining an electrical connection between the contact and the wiring. 
         [0053]    In one embodiment, the wires extend into the sealing cover through a wiring harness  62  mounted within the distal end of the sealing covers. Specifically, the wiring harness  62  is sized to fit within the distal end of the hollow cavity of the plug and receptacle. As illustrated in  FIGS. 2 and 4 , the wiring harness  62  may be cylindrical in shape with a plurality of holes passing therethrough. The holes are sized to support wiring therethrough and may contain a plurality of ridges to frictionally engaged insulation around the wiring. In one embodiment, the wiring harness  62  may be secured within the hollow cavity of the sealing cover by a plurality of ridges. The ridges  64  may be adapted to frictionally engage the wiring harness  62  so as to frictionally hold it in a plane perpendicular to the longitudinal axis of the sealing cover. Alternatively, the ridges may be adapted to threadingly engage the wiring harness  62  so as to secure it within the sealing cover. The wiring harness is not limited to the foregoing embodiments and may be in any similar configuration to secure the wiring to the sealing cover and maintain the connection between the wiring and the contacts. 
         [0054]    In operation, the contact  58  of each cartridge block  16  is placed into electrical communication with a wire in accordance with the above and the cartridge blocks  16  or block units  12  are secured within each of the plug  2  and receptacle  4 . The frictional engagement of the cartridge blocks  16  with the interior walls of the respective cartridge chambers and the alignment features  37  serve the secure all of the cartridge blocks therein so as to display the proximal end of each cartridge block  16  and contact  58  at the proximal ends of the plug  2  and receptacle  4 . Moreover, bonding the cartridge blocks into discrete units  12  facilitates the installation and removal of the cartridge blocks into and out of the sealing covers. 
         [0055]    As illustrated in  FIGS. 1 and 11 , the cartridge blocks  16  are positioned within the plug and receptacle such that the distal end of each cartridge block abuts the retaining walls  40   a ,  40   b  and electrical wiring, extending into the distal end of the sealing covers, may be coupled to the distal end of each contact. To prevent the wiring from separating from the distal end of the contact the wiring is further secured to the sealing covers  14   a ,  14   b , by way of the wiring harness  62 . 
         [0056]    As noted above, each of the cartridge the blocks  16  within the plug  2  represent interlocking halves with each of the cartridges blocks  16  of the receptacle  4 . To this end, when installed, the cartridge blocks of the plug are positioned in an inverted orientation to those of the receptacle such that the channels of each cartridge block  16  of the plug  2  receive the contacts of the cartridge blocks  16  of the receptacle  4  and vice versa. Referring to  FIG. 5 , when the plug and receptacle are connected, the electrical contacts of the plug  2  and receptacle  4  are received by the channels of the opposing cartridge blocks and are placed into electrical communication therewithin. More importantly, when the plug and receptacle are mated, the housings  56  within the plug and receptacle completely overlap such that both contacts are completely encased within the overlapping housings. Thus, the overlapping cartridge blocks of the plug and receptacle provide a first insulative layer for the electrical contact between the plug and receptacle. A second insulative layer is provided the sealing covers  14   a  and  14   b  wherein, when the plug and receptacle are mated together, the respective sealing covers interconnect in accordance with the above so as to isolate the cartridge blocks from environmental conditions. 
         [0057]    Based on the foregoing, the present invention is advantageous because it provides a plurality of electrical connections within a plug and receptacle system wherein the electrical connections are completely insulated from environmental conditions. More specifically, the housing  56  surround each contact in the plug and receptacle mate such that the housing, in combination, completely surround and encase the electrical connection therein. This connection is further protected by way of the sealing covers of the plug and receptacle, which also overlaps so as to isolate the housings and electrical connections from environmental conditions. 
         [0058]    The present invention is additionally advantageous because the electrical connections of both the plug and receptacle may be easily replace. Specifically, one desiring to replace an electrical contact can easily remove a cartridge block  16  or cartridge unit  12  from a sealing cover. Replacing the cartridge block  16  or unit  12  involves nothing more than securing the block  16  or unit  12  to the wiring and reattaching it within the sealing cover. Accordingly, replacement of the electrical contact is relatively simple. 
         [0059]    Additional advantages that are apparent to one of ordinary skill in the art are also included herein.