Abstract:
A wire harness for preventing water from contacting capped, connected electrical wires. A lid and a base define an interior chamber. The base has fingers extending vertically upwardly for holding wire caps and connected electrical wires therein. A shelf protrudes from the inner surface of each finger to provide a platform for the bottom edge of the wire cap to seat against, securing the wire cap against downward movement. The sidewalls of the lid extend a predetermined distance below the shelves of the fingers to form a rim that creates a double air trap within the harness for preventing water from contacting the conductive portions of the wires.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
   (Not Applicable) 
   STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT 
   (Not Applicable) 
   REFERENCE TO AN APPENDIX 
   (Not Applicable) 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates generally to wire harnesses and more particularly to a protective wire harness enclosure for preventing electrical wires from coming into contact with water. 
   2. Description of the Related Art 
   Conventional wire harnesses are routinely implemented in a variety of electrical systems, such as those employed in motor vehicles. Such harnesses are used for the convenient assembly and organization of a collection of interconnected electrical wires, as well as for protecting those wires from potentially harmful conditions that may exist outside the harness, such as flooding. 
   Despite the use of a conventional harness, the exposed connective sections of wires within a harness remain susceptible to water contact due to harness structural failures such as leakage or breakage. This is highly undesirable, as exposure of live electrical wires to water may cause overcurrent conditions that may disrupt or damage an electrical system. 
   BRIEF SUMMARY OF THE INVENTION 
   It is an object and feature of the present invention to provide a wire harness that not only secures and shields the interconnected electrical wires disposed therein, but that has an improved interior configuration that provides a double air trap for preventing water-to-wire contact. 
   In accordance with the present invention, there is provided a harness having a lid and a base defining a chamber. The lid has a top wall and an upper enclosure, and the upper enclosure has a ceiling and four adjoining side walls that define an upper chamber. The four side walls extend vertically downwardly from the ceiling, passing through and extending below the top wall, terminating at a bottom rim. The rim defines an opening that is part of a contiguous empty space extending from below the top wall into the upper chamber. 
   One or more fingers extend vertically upwardly from the base into the upper chamber. Each finger has a channel within it for holding a vertically oriented wire cap and a set of at least two interconnected electrical wires. The connective ends of the wires (i.e. the unsheathed portions of the conductors) are engaged by the wire cap. Furthermore, a shelf protrudes into the channel from the inner wall of each finger, and extends upwardly from the base. The top of the shelf provides an upwardly facing platform for the lower edge of the wire cap to seat against. 
   The platform created by each shelf, and therefore the bottom edge of each wire cap that is seated on a shelf, is disposed within the harness above the bottom rim. This configuration provides two air traps within the harness, one within the upper chamber and one within each wire cap. These traps prevent any water that may enter the harness from rising above the lower edges of the air traps, thereby preventing water from contacting the connective portions of the wires therein. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  is a side cross-sectional view illustrating the preferred embodiment of the present invention. 
       FIG. 2  is a front cross-sectional view illustrating the preferred embodiment of the present invention. 
       FIG. 3  is a perspective view illustrating the preferred embodiment of the present invention with a cut-out view of the upper enclosure portion. 
   

   In describing the preferred embodiment of the invention which is illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific term so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word connected or term similar thereto are often used. They are not limited to direct connection, but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art. 
   DETAILED DESCRIPTION OF THE INVENTION 
   As shown in  FIGS. 1-3 , the harness  10  has a lid  12  and a base  14  which fit securely together to close the harness  10 . This forms a watertight seal at the lid-base juncture  16  for preventing water from entering the harness  10 . 
   The lid  12  of the harness is a unitary body having a top wall  32 , an upper lip  34 , and an upper enclosure  36 . The upper enclosure  36  has a rectangular ceiling  38  and four sidewalls  40 ,  42 ,  44 , and  46  extending downwardly and attached to each other at adjoining edges defining an upper chamber  48 . Other shapes can be substituted for the preferred shape. The ceiling  38  is parallel to the top wall  32 . Each of the sidewalls  40 - 46  extends vertically downwardly from a respective edge of the ceiling  38 , passing through and extending below the top wall  32  of the lid  12  and terminating at a bottom rim  50 . The bottom rim  50  is positioned approximately halfway between the top wall  32  and a floor  24  as discussed below, although this distance is not critical so long as there is at least enough space left between the bottom rim  50  and the floor  24  for wire to pass through. The bottom rim  50  defines an opening that is part of a contiguous empty space extending from below the top wall  32  into the upper chamber  48 . Wire can pass through this empty space. 
   The base  14  of the harness  10  is a unitary body having a floor  24 , a lower lip  26 , and two fingers  28  and  30 . The fingers  28  and  30  are formed from adjoining finger walls  52 ,  54 ,  56 ,  58 , and  60 . One of the walls  56  is shared by both fingers  28  and  30 . The finger walls  52 - 60  extend vertically upwardly from the floor  24 , past the bottom rim  50  and into the upper chamber  48 , terminating at a point close to the ceiling  38 . The finger walls  52 - 60  form channels  62  and  64 , each of which holds one of the vertically oriented wire caps  66  and  68  and at least two electrical wire pairs  20  and  22  with conventional sheathing covering conductor pairs  70  and  72 . The wire pairs  20  and  22  are a pair of separate conductors that have been joined together, and are given one reference number per pair. The interconnected conductor pairs  70  and  72  are disposed within, and are securely engaged by, their respective wire caps  66  and  68 . 
   Depending upon the application, there can be as few as one finger or as many fingers as are deemed necessary to implement a particular design. Each finger can have more than three sidewalls. Furthermore, the fingers  28  and  30  may comprise one unitary body, sharing a wall as depicted in  FIGS. 1 and 3 , or the walls may be separate from each other. Thus, it will become apparent that many alternatives to the preferred fingers  28  and  30  are contemplated. 
   The shelves  74  and  76  extend upwardly from the base  14  and protrude from the inner wall of each of the fingers  28  and  30  into the respective channels  62  and  64 , providing upwardly facing platforms  78  and  80 , respectively, for the lower edges of the wire caps  66  and  68  to seat against. The shelves  74  and  76  extend to a height that is determined by the wire cap height and the height of the ceiling  38 . When the lower edges of the wire caps  66  and  68  are seated on the shelves  74  and  76 , the top or closed ends of the wire caps  66  and  68  protrude above the tops of the fingers  28  and  30  to, or just beneath, the ceiling. 
   A primary air trap is created within the upper chamber  48 . Therefore, if water enters the harness  10 , causing the water level inside the harness  10  to rise from the floor  24  upward to the bottom rim  50 , the air occupying the space inside the upper chamber  48  will have nowhere to escape to. The air will therefore continue to occupy the space inside the upper chamber  48 , despite increased pressure, and will prevent water from entering the upper chamber  48 . The air trap keeps the conductor pairs  70  and  72  inside the upper chamber  48  dry. The upper chamber  48  thus acts in the same manner as a diving bell, keeping water from entering a downwardly facing cavity filled with air. 
   It is a critical feature of the harness  10  that the shelves  74  and  76 , and therefore the bottom edges of the wire caps  66  and  68  seated on the shelves  74  and  76 , be disposed within the harness  10  above the bottom rim  50 . In the event that water should somehow enter the upper chamber  48 , each wire cap  66  and  68  forms a secondary air trap. If water rises above the bottom rim  50  and reaches the lower edges of the wire caps  66  and  68 , the air inside the wire caps  66  and  68 , unable to exit the top closed ends of the wire caps  66  and  68 , will have nowhere to escape. The air will therefore continue to occupy the space inside the wire caps  66  and  68 , despite increased pressure, and will prevent water from entering the wire caps  66  and  68  from the bottom open ends. The air trap will thereby prevent water from contacting the conductor pairs  70  and  72  therein. It should be noted that although a double air trap configuration has been described, embodiments of the invention employing three or more air traps are also contemplated. For example, another chamber having another rim can be formed within the upper chamber  48 . 
     FIG. 2  shows a structure that can be added to the invention, in which a flange  82  is employed to help secure the seated wire caps  66  and  68  against vertical and horizontal movement. The flange  82  has a concave surface and extends from the ceiling  38  to a sidewall  42 . When the harness  10  is closed, the flange  82  fits snugly against the tops of the wire caps  66  and  68 , applying vertical and horizontal pressure to them to firmly seat them against the platforms  78  and  80 , thereby preventing them from shifting within their respective channels  62  and  64 . Flanges having other shapes and, more generally, any other methods for securing the wire caps against movement within their respective channels, are also contemplated by this invention. 
   In a typical application, the harness  10  is mounted within the engine compartment of a motor vehicle, such as an automobile or a watercraft. However, the harness  10  may be employed in any application in which it is desirable to reduce the risk of water to wire contact. The harness  10  may be made from any rigid, watertight material, but is preferably constructed from a plastic such as acrylonitrile butadiene styrene (ABS) using conventional manufacturing methods such as injection molding. The dimensions of the harness  10  will vary from application to application based on design constraints such as the space available for the harness  10  and the number of wires that must be accommodated by the harness  10 . 
   To implement the harness  10 , wire pairs  20  and  22 , having cut and stripped connective conductor pairs  70  and  72 , are drawn from various electrical components of the subject system (i.e. automobile, watercraft, etc.) into the open harness  10 . The conductors that are to be interconnected are grouped together and capped in a conventional manner using conventional wire caps  66  and  68 . The wire caps  66  and  68  are of a size small enough to fit within the portions of the channels  62  and  64  above the platforms  78  and  80  but not so narrow that they can fit within the portions of the channels  62  and  64  below the platforms  78  and  80 . The shielded segments of the wire pairs  20  and  22  are then pressed into the channels  62  and  64  with the wire pairs  20  and  22  extending from the bottoms of the channels  62  and  64  toward the tops of the channels  62  and  64 . The conductor pairs  70  and  72  and their respective wire caps  66  and  68  protrude above the upwardly facing platforms  78  and  80  with the wire caps  66  and  68  seated on their respective upward facing platforms  78  and  80 . The harness  10  is then closed and latched via hinge  84  and latch  86 , creating a seal at the lid-base juncture  16 . 
   Under normal operating conditions, the harness  10  will remain watertight while closed. However, circumstances may arise in which water is allowed to enter the harness  10 , e.g. the harness may be damaged, or the seal at the lid-base juncture  16  may be compromised, resulting in leakage. In such a situation, the above described double air trap configuration of the present invention will prevent the incoming water from contacting the conductor pairs  70  and  72  inside the wire caps  66  and  68 , thereby preventing electrical fault conditions that could disrupt or damage the operation or components of the subject system. 
   Many alternatives to the fingers  28  and  30  exist and are contemplated by the invention. Any means for securely holding vertically oriented wire caps within the upper chamber  48  will suffice, including arms or clamps protruding from the ceiling  38  or from the sidewalls  40 ,  42 ,  44 , and  46 , or an adhesive holding the wire caps to the ceiling  38  or to the sidewalls  40 ,  42 ,  44 , and  46 . 
   While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims.