The invention relates to a wire connector assembly, more particularly, a wire feed-through connector assembly containing provisions that allow use of the wire connector assembly in fluid environments.
Some electrical applications require submersion of a wire connector assembly in a fluid environment. One example of a wire connector assembly includes wire conductors formed with an inner core that has individual wire strands covered by an insulative outer covering. A portion of the wire conductors are stripped free of the insulation covering and the stripped areas are subsequently tinned with solder. Tinning the wire strands fuses the wire strands together by forming a coat of solder on the wire strands resulting in a single, solid core wire connection. The tinned solid core wire connection creates a dam that acts as a leakage barrier to impede fluid flow into, and through the individual wire strands. The tinned solid core connections of the wire conductors are then over-molded with an electrically nonconductive material to form a molded connector body. The molded connector body is subsequently attached to a support structure within the fluid environment. This wire connector assembly design has several drawbacks. One drawback is that the solder may wick into the wire stands so that a tinned portion of the wire strands extend beyond a boundary of the molded connector body. This causes a portion of the wire conductor to be mechanically stiffer than the remaining wire conductor which reduces the flexibility and increases a bend radius of the wire conductor at the molded connector boundary which may inhibit a tight routing path desired in some electrical applications.
Other known wire connector configurations rely on the use of gaskets and/or glass-to-metal seals that increase the complexity of the wire connector assembly while undesirably adding increased cost to the wire connector assembly.
The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also be inventions.
In accordance with one embodiment of this invention, a wire connector assembly is provided. The wire connector assembly includes a connector body formed of a dielectric material and a plurality of wire cables formed of an electrically conductive inner core surrounded by an electrically insulative outer covering. Each wire cable has an outer covering end portion removed to expose an inner core end portion. Each inner core comprises a plurality of wire strands. The wire connector assembly further includes a wire splice element electrically and mechanically joining at least two inner core end portions. The at least two inner core end portions are axially spaced apart. The connector body encloses the wire splice element and sealably engages each outer covering of the plurality of wire cables.
The plurality of wire cables, the wire splice element, and the connector body may provide a fluid resistant electrically conductive path through the wire connector assembly. A portion of the connector body may be disposed intermediate to the at least two inner core end portions to provide a barrier to a fluid infiltrating the inner core of one of the plurality of wire cables.
The wire splice element may define a plurality of wire crimp wings. The wire crimp wings may be axially spaced apart. The wire splice element further may define a plurality of insulation crimp wings configured to retain the outer covering. The plurality of insulation crimp wings may be distinct from the plurality of wire crimp wings.
In another embodiment of the present invention, a method to fabricate a wire connector assembly is provided. The method includes the step of providing a plurality of wire cables and a wire splice element, wherein the plurality of wire cables are formed of an electrically conductive inner core surrounded by an electrically insulative outer covering. The method further includes the steps of removing the outer covering from an end of each wire cable to expose the inner cores of the plurality of wire cables, inserting the end of each wire cable in the wire splice element, electrically and mechanically attaching the end of each wire cable to the wire splice element to form a wire arrangement, inserting the wire arrangement into a mold, injecting a dielectric material in a fluid state into the mold to surround at least a portion of the wire arrangement containing the wire splice element to form the wire connector assembly, and hardening the dielectric material to a solid state, thereby forming a connector body. The connector body encloses the wire splice element and sealably engages the outer covering of the plurality of wire cables.
The wire splice element may define a plurality of wire crimp wings and the step of electrically and mechanically attaching the end of each wire cable to the wire splice element may further include the step of crimping the plurality of wire crimp wings to the end of each wire cable. The wire crimp wings may be axially spaced apart.
The step of injecting the dielectric material into the mold may include the step of injecting a portion of the dielectric material intermediate to the end of each wire cable to provide a barrier to a fluid infiltrating the inner core of one of the plurality of wire cables.
The wire splice element may further define a plurality of insulation crimp wings configured to retain the outer covering and the step of electrically and mechanically attaching the end of each wire cable to the wire splice element may include crimping the plurality of insulation crimp wings to the outer cover of each wire cable. The plurality of insulation crimp wings may be distinct from the plurality of wire crimp wings.
The step of inserting the wire arrangement into the mold may further include the step of arranging a plurality of wire arrangements in the mold so that the plurality of wire arrangements are electrically independent one-to-another.
Further features and advantages of the invention will appear more clearly on a reading of the following detailed description of the preferred embodiment of the invention, which is given by way of non-limiting example only and with reference to the accompanying drawings.
The present invention will now be described, by way of example with reference to the accompanying drawings, in which:
a is a side view of a wire splice element used in the wire connector assembly of
b is a top view of a wire splice element used in the wire connector assembly of
When used in the fuel tank 16 shown in
As shown in the non-limiting example of
As shown in the non-limiting example of
A first inner core 34 end portion of one of the first plurality of wire cables 26 is electrically and mechanically joined to a second inner core 34 end portion of one of the second of wire cables 28 by a wire splice element 32 to form a wire arrangement 38. In the illustrated example, the first inner core 34 end portion and the second inner core 34 end portion are axially spaced apart. Alternatively, other embodiments of the assembly 10 may be envisioned in which the first inner core 34 end portion and the second inner core 34 end portion are non-axially spaced apart, for example the end portions may be axially offset from each other or the end portions may be arranged perpendicular to each other.
In this non-limiting example, the wire splice element 32 defines a plurality of wire crimp wings 40 that are configured to be mechanically and electrically connected to the first inner core 34 end portion and the second inner core 34 end portion. The plurality of wire crimp wings 34 are spaced apart so that when the first and second inner core 34 portion are joined to the wire splice element 32, the first inner core 34 end portion and the second inner core 34 end portion are spaced apart. Without subscribing to any particular theory of operation, fluids may enter the wire cables 26, 28 through tears or openings in the outer covering 36 and flow though spaces or voids between the wire strands of the inner core 34. Because the ends of the wire cables 26, 28 are spaced apart, or separated, fluid entering the first wire cable 26 cannot directly continue its flow path to enter the second wire cable 28.
The design of wire splice elements 32 having wire crimp wings 34 and the methods used to mechanically and electrically attach wire splice elements 32 to wire cables 26, 28 are well known to those skilled in the art. While this example illustrates a wire arrangement 38 having two wire cables 26, 28 joined by a single wire splice element 32, other embodiments may be envisioned wherein three or more wire cables are joined by a single wire splice element 32.
As shown in the non-limiting example of
The connector body 30 may be formed of a dielectric polymer material, such as polyamide (NYLON) or polybutylene terephthalate (PBT). Alternatively, the connector body 30 may be formed from an epoxy-based dielectric material that chemically bonds with the outer covering 36 of the wire cables 26, 28 and further seals the assembly 10 against fluid leakage entering the assembly 10. The epoxy-based material may provide more robust performance in an application where the assembly 10 will be exposed to chemicals or hydrocarbons because the epoxy-based material is less likely to soften or chemically break down over a time period when disposed these in these types of applications.
The wire connector assembly 10 may be useful in the motorized transportation industry such as electrically connecting fuel level sensors in fuel tank applications, or in other industries like chemical processing, or oil and gas exploration where electrical connections must cross a boundary of two different environments. Flame retardant and/or low toxicity plastic materials may be utilized to construct the connector body 30 when the assembly 10 is used for aerospace applications.
As illustrated in the non-limiting example of
The wire arrangements 38a-d are axially disposed within the connector body 30 and include wire splice elements 32a-d respectively disposed in connector body 30. Wire splice elements 32a-d are formed from an electrically-conductive material, such as a copper alloy or steel. The first inner core 34 end portions of the first plurality of wire cables 26a-d are disposed in one end of the wire splice elements 32a-d and are in intimate contact with the wire crimp wings 34 and the second inner core 34 end portions of the second plurality of wire cables 28a-d are disposed in the opposite end of the wire splice elements 32a-d and are in intimate contact with the wire crimp wings 34. The first inner core 34 end portions, the second inner core 34 end portions, and the wire splice elements 32a-d are enclosed by connector body 30. Wire splice elements 32a-d are further spaced apart one-to-another in a direction perpendicular to axis A within connector body 30 being spaced apart by portions of connector body 30, as best illustrated in
a and 5b illustrate a non-limiting example of a wire splice element 32. The wire splice element 32 defines an axis B along a length L2 of wire splice element 32. Length L2 is less than length L1 of the connector body 30. Axis B is typically parallel with axis A when wire splice element 32 is disposed in wire connector assembly 10 with other wire splice elements 32, as best illustrated in
The connector body 30 may preferably be formed by molding the dielectric material around the wire arrangements 38. When the dielectric material is injected or poured in a fluid form into a mold containing the wire arrangements 38, the dielectric material may flow into the open connecting portion 44 and after the dielectric material hardens into a solid form, a portion of the connector body 30 is disposed intermediate to the inner core 34 end portions.
Referring to
The examples of the assembly 10 illustrate a configuration wherein the wire arrangements 38 are side-by-side. Alternatively, embodiments of the assembly 10 with other configurations of wire arrangements 38 may be envisioned. This may include, but is not limited to, an array of wire arrangements 38 within the connector body 30. One array may include wire arrangements 38 arrayed in rows and columns. An alternative array may have a staggered row arrangement. Alternatively, the assembly 10 may contain a single wire arrangement 38.
STEP 110, PROVIDE A PLURALITY OF WIRE CABLES AND A WIRE SPLICE ELEMENT, includes providing a plurality of wire cables 26.28 and a wire splice element 32. The plurality of wire cables 26, 28 are formed of an electrically conductive inner core 34 surrounded by an electrically insulative outer covering 36. The wire splice element 32 may define a plurality of wire crimp wings 34 configured to mechanically and electrically attach the wire splice element 32 to the inner core 34 of the wire cables 26, 28. The wire crimp wings 34 may be spaced apart from each other. The wire splice element 32 may also define a plurality of insulation crimp wings 46 configured to retain the outer covering. The plurality of insulation crimp wings 46 may be distinct from the plurality of wire crimp wings 34.
STEP 112, REMOVE THE OUTER COVERING FROM AN END OF EACH WIRE CABLE, includes removing the outer covering 36 from an end of each wire cable 26, 28 to expose the inner cores 34 of the plurality of wire cables 26, 28 by cutting away a portion of the outer covering 36.
STEP 114, INSERT THE END OF EACH WIRE CABLE IN THE WIRE SPLICE ELEMENT, includes inserting the end of each wire cable 26, 28 in the wire splice element 32. A first wire cable 26 and a second wire cable 28 may be inserted into the wire splice device 32 manually by a human assembly operator when at least one wire arrangement 38 is manually constructed.
STEP 116, ATTACH THE END OF EACH WIRE CABLE TO THE WIRE SPLICE ELEMENT, includes electrically and mechanically attaching the end of each wire cable 26, 28 to the wire splice element 32 to form a wire arrangement 38. At least one wire arrangement 38 is formed when the exposed ends of the inner metallic core 34 of the wire cables 26, 28 are electrically and mechanically attached to wire splice element 32.
Step 116 may optionally include STEP 118, CRIMP THE PLURALITY OF WIRE CRIMP WINGS TO THE END OF EACH WIRE CABLE which includes crimping the plurality of wire crimp wings 34 to the exposed end of each wire cable 26, 28. The crimping may result in a hermitic crimp that will reduce the spaces and void between the individual wire strands and create a barrier to fluid flow through ends of the inner cores 34 of the wire arrangement 38. The wire crimp wings 34 may be attached to the end of each wire cable 26, 28 using a crimping press as is also well known to those skilled in the art.
Step 116 may optionally include STEP 120, CRIMP THE PLURALITY OF INSULATION CRIMP WINGS TO THE OUTER COVER OF EACH WIRE CABLE, which includes crimping the plurality of insulation crimp wings 46 to the outer covering 36 of each wire cable 26, 28. The insulation crimp wings 46 may be attached to the outer covering 36 using a crimping press as is also well known to those skilled in the art. Crimping the plurality of insulation crimp wings 46 to the outer covering 36 of the wire cables 26, 28 may prevent the outer covering 36 from shifting or pulling back from the wire ends and may ensure that the insulation does not “pull back” 52 and expose the wire strands of the inner core at the surface of the assembly 10 as shown in
STEP 122, INSERT THE WIRE ARRANGEMENT INTO A MOLD, includes inserting the wire arrangement 38 into a mold within a molding machine 50.
Step 122 may optionally include STEP 124, ARRANGE A PLURALITY OF WIRE ARRANGEMENTS IN THE MOLD, which includes arranging a plurality of wire arrangements 38a-c in the mold so that the plurality of wire arrangements 38, a-c are electrically independent one-to-another. The plurality of wire arrangements 38a-c may be placed into a fixture 48 to hold plurality of wire arrangements 38a-c in place before being placed into the mold as shown in
STEP 126, INJECT A DIELECTRIC MATERIAL IN A FLUID STATE INTO THE MOLD, includes injecting a dielectric material in a fluid state into the mold using a molding machine 50 to surround at least a portion of the wire arrangement 38 containing the wire splice element 32 to form the wire connector assembly 10.
Step 126 may optionally include STEP 128, INJECT A PORTION OF THE DIELECTRIC MATERIAL INTERMEDIATE TO THE END OF EACH WIRE CABLE, which includes injecting a portion of the dielectric material that forms the connector body 30 into the connecting portion 44 of the wire splice element 32 intermediate to the end of each wire cable 26, 28 to provide a barrier to a fluid infiltrating the inner core 34 of one of the plurality of wire cables 26, 28.
STEP 130, HARDEN THE DIELECTRIC MATERIAL TO A SOLID STATE, includes hardening the dielectric material to a solid state, thereby forming a connector body 30, wherein the connector body 30 encloses the wire splice element 32 and sealably engages the outer covering 36 of the plurality of wire cables 26, 28.
Accordingly, a wire feed-through connector assembly 10 that is configured to operate in fluid environments and a method 100 of constructing a wire feed-through connector assembly is provided. The assembly 10 provides electrical conductivity of the wire cables 26, 28 end-to-end through the connector body 30 of the assembly 10 in gaseous fluid environments 18, liquid fluid environments 24, or a combination of these environments. The assembly 10 inhibits fluid leakage through the wire strands of the inner core 34 of the wire cables 26, 28 because the ends of the wire cables 26, 28 are spaced apart and joined by a wire splice element 32, forming a physical barrier to fluid continuing a path through the assembly 10. Further, a portion of the connector body 30 is disposed between the ends of the wire cables 26, 28, providing an additional physical barrier to a fluid leak path through the assembly 10. The assembly 10 uses no solder in its construction, thus, there is no undesirable wicking of solder into portions of the wire cables 26, 28 outside the connector body 30. The insulation crimp wings 46 secure the ends of the outer covering, preventing pull back of the outer covering that may result in exposed wire stands near the first portion 20 or the second portion 22 of the connector body 30.
While this invention has been described in terms of the preferred embodiments thereof, it is not intended to be so limited, but rather only to the extent set forth in the claims that follow. Moreover, the use of the terms first, second, etc. does not denote any order of importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
This application is a continuation-in-part application and claims the benefit under 35 U.S.C. §120 of U.S. patent application Ser. No. 13/423,325, filed Mar. 19, 2012, which claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/514,951, filed Aug. 4, 2011, the entire disclosure of which is hereby incorporated herein by reference.
Number | Date | Country | |
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61514951 | Aug 2011 | US |
Number | Date | Country | |
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Parent | 13423325 | Mar 2012 | US |
Child | 13757201 | US |