Patent Description:
Electrical connectors, or terminals for terminating a power cable connection, are often connected side-by-side to grounding studs, to power strips or on top of each other, such as on a terminal block or on a power strip. They provide power to circuitry and electronics of a system, vehicle, or device, and thus, are often coupled in a tight configuration to address space constraints, such as in an aircraft. The phrases lug, terminal lug, and terminal will be used interchangeably in this application to refer to such terminal connectors.

While wire and cables that are terminated with such terminal are insulated along their length, the terminals themselves are exposed for making electrical contact with other terminals, terminal blocks, or equipment connection points. As a result, arcing can occur between adjacent terminals. Electrocution is also a possibility with such exposure.

The problem with shorting or arcing has become a particular problem within the aerospace industry. Most new airframes are being designed to eliminate hydraulic systems and to replace those systems with electro-mechanical actuators. Also, recent advancements have led to the use of higher electrical voltages and frequencies in an aircraft. Greater us of electrical systems and the respective higher voltages and frequencies directly impact the likelihood of accidental shorting and arc tracking at the terminal connection points. Accidental shorting or arcing between the different voltage phases that are used in such systems can cause damage, and may potentially shut the power down for a system. Furthermore, space constraints exacerbate the issue as the terminals are often positioned close to one another at a terminal block or at equipment connection points. Still further, passenger comfort has led to greater humidity in the environment of the electrical systems.

Contaminants between the terminals may also cause arcing issues. Various dry, liquid, or vapor contaminants have the potential to create an electrical path between terminals under dry, humid, or wet conditions. If the various contaminants can create a low enough current resistance paths between the terminals, then arc tracking may start and progress to the point of significant damage.

There have been various existing methods to try to isolate the terminals in order to prevent arcing. However, such methods often involve mechanical dividers or require increasing separation distances, which may not always be feasible. However, such existing methods have been optimized, and, even with current precautions, the existing elements and methods may still allow the conductive surfaces of the terminal to get close enough to each other to allow arc tracking. The various physical dividers are not sufficient to prevent the arc tracking.

Furthermore, the issue of changing or reconfiguring a connection is often complicated by the insulative or sealing environment. The material, such as molten insulation material, that is applied to the connections and terminals once they are secured is usually of a permanent nature. To disconnect the terminal or to attach additional terminals, the material has to first be removed. Then, once the new connection configuration is complete, the material has to again be applied.

Accordingly, it is an objective of the invention to address arcing concerns between adjacent electrical terminals. It is further the objective to prevent arcing while not compromising the terminal's function. It is a further objective to improve on the configuration and configurability of such terminal connections. The present invention addresses these objectives and various drawbacks in the prior art.

<CIT> discloses a plastic sealing sleeve for a conductor connection between a first conductor and a second conductor, wherein, in the connection state, the first conductor is connected to the second conductor by means of a mandrel which produces a conductive connection, and the mandrel passes through an insertion region of the first conductor. In order to further improve such a sealing sleeve, the sealing sleeve can be slipped over the first conductor and, at its end associated with the insertion region of the first conductor, said sealing sleeve comprises a receiving region that is completely enclosed, transversely to a direction of passage, for the first conductor, and a through-opening in the direction of passage, wherein the through-opening in the direction of passage comprises a first and a second opening edge and has a closed peripheral sealing lip at least on the second opening edge and, at its end facing away from the connection region, the sealing sleeve is configured for a sealing interaction with the first conductor.

<CIT> is considered to be the prior art closest to the subject-matter of independent claim <NUM> and discloses an electrical terminal for coupling to a conductive structure, the electrical terminal comprising:.

An electrical terminal for coupling to a conductive structure includes a body having a wire receiving portion for receiving a conductor. A cup portion is electrically coupled with the wire receiving portion and a boss portion extends from the cup portion. The boss portion and includes an exposed planar surface for interfacing with the conductive structure. An overmold structure of insulation material is formed on the cup portion and covers the cup portion sides. An aperture is formed in the body and extends through the cup portion and the boss portion for receiving a post of the conductive structure for securing the terminal to the conductive structure. A fastener is configured for engaging a post and securing the boss portion against the conductive structure. The boss portion is configured to surround the aperture for providing an electrically conductive surface free from insulation material for interfacing with the conductive structure. The fastener and post are contained in the cup portion and an insulative cap is configured for engaging the overmold structure and sealing the cup structure around the fastener and post of a conductive structure.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given below, serve to explain the principles of the invention.

It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the sequence of operations as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes of various illustrated components, will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration.

With reference to <FIG>, an arc resistant electrical terminal <NUM> in accordance with features of the invention is incorporated into a cable or wire assembly <NUM>. The arc resistant terminal <NUM> includes a body made from a suitable electrically conductive material, such as a metal such as copper or aluminum. In one embodiment, terminal <NUM> is a solid piece of <NUM> Aluminum per ASTM B221. The terminal has a body with a solid or integral construction and includes a wire receiving portion <NUM> and an integral mount portion <NUM>. The terminal <NUM> is incorporated into the cable assembly <NUM> with a suitable wire or conductor <NUM>, as shown in <FIG>. Conductor <NUM>, for example, might be a solid or stranded copper or aluminum wire having a center conductor <NUM> and an insulating sheath <NUM>. In one embodiment, the conductor <NUM> connected with the terminal may also include an abrasion sheath <NUM>.

Referring to <FIG> and <FIG>, embodiments of an arc-resistant terminal are illustrated. Terminal <NUM> includes a body defining the wire receiving portion <NUM> that has a front face <NUM> including an aperture <NUM>, a back face or wall <NUM>, and an outer wall <NUM> between the front face <NUM> and the back face <NUM>. The receiving portion <NUM> thus has an open end and a sealed end and is configured to receive the end of a conductor <NUM>. As illustrated, the receiving portion <NUM> is show as cylindrical, consistent with the usual cylindrical shape of a wire; however, the receiving portion <NUM> also may be a variety of other shapes. Between the back face <NUM> of the receiving portion <NUM> and the integral mount portion <NUM> is a transition radius or section <NUM> that transitions to the mount portion <NUM>.

For connecting the terminal <NUM> to a suitable structure at an electrical connection point, such as a terminal block (see <FIG>), the mount portion has a leg or tongue <NUM> which may be formed of a solid conductive metal. In the illustrated embodiment, the tongue is referred to as an RT, ring tongue, or sealed tongue configuration. The tongue <NUM> defines opposing face surfaces, including a top face surface <NUM> and a bottom face surface <NUM> that, in one embodiment, are oriented approximately parallel to an axis <NUM> of the receiving portion <NUM> of the terminal <NUM>. The tongue <NUM> in the illustrated embodiment is offset and oriented in a plane below the axis <NUM>. In the embodiment of <FIG>, <FIG>, an aperture or hole <NUM> is formed between the face surfaces <NUM>, <NUM> for connecting the terminal to a connector port either individually or with another terminal overlaid with it as illustrated in <FIG>. The aperture <NUM> passes through the leg <NUM> of the mount portion <NUM> and extends from the top face surface or face <NUM> to the bottom face surface or face <NUM>. The receiving portion <NUM> also has a top <NUM> and a bottom <NUM>, as determined by the orientation of the top face <NUM> and bottom face <NUM> of leg <NUM>. The receiving portion <NUM> is configured to be crimped onto wire or conductor <NUM>.

In accordance with one feature not forming part of the invention, the arc-resistant terminal <NUM> incorporates a leg or tongue <NUM> which has raised or elevated bosses 220a, 220b surrounding the aperture <NUM>. The raised base is formed to surround the aperture on an opposing face surface. In a particular embodiment, the bosses are positioned both at the top face surface <NUM>, and the bottom face surface <NUM> of tongue <NUM>, as shown in <FIG>. The bosses 220a, 220b are preferably integrally formed with the tongue <NUM> to extend above the respective face surfaces <NUM>, <NUM> surrounding aperture <NUM>. However, as shown in <FIG>, the one or more of the bosses 223a, 223b might be configured as a separate element that is used in conjunction with and mounted with the tongue <NUM> to provide the present invention and advantages thereto.

Referring to <FIG>, the height H of a boss 220a, 220b may be in the range of <NUM> inch (<NUM>) to <NUM> inch (<NUM>) above a respective face surface <NUM>, <NUM>. The bosses surround the aperture and in illustrated embodiments the bosses are generally circular around aperture <NUM> to surround the aperture. The bosses may have other shapes as well to surround the aperture <NUM>. In the illustrated embodiment, the outer diameter D of the circular boss may be in the range of <NUM> inches (<NUM>) larger in diameter than the aperture <NUM> and up to the full width of the tongue <NUM>. Optimally, the diameter D is the same or greater than the size of the washer <NUM> under a nut <NUM>. The size of the bosses will depend on the overall size of aperture <NUM>, and the gauge of the stud or bolt <NUM> extending through aperture <NUM>, as illustrated in <FIG>. Generally, the bosses provide suitable electrically conductive surfaces <NUM> that form an electrical connection with a terminal bar or block <NUM>, or other connection point structure to which the cable assembly <NUM> and terminal <NUM> are coupled. The bosses 220a, 220b are configured and sized to provide sufficient connection to the metal areas on a terminal block, other terminal, or connection point to which the terminal <NUM> is secured. For example, the bosses might be configured and sized based on the size of a post <NUM> and respective nut <NUM> and washer <NUM> combination (See <FIG> or <FIG>, <FIG>. <FIG> illustrates a nut and washer combination for securing the tongue. A lock washer (not illustrated) or a specifically designed lock nut might be implemented in the securing arrangement for further securing the tongue in place. The size of the washer <NUM> and boss 220a, b is selected to ensure good electrical contact. The outer range of the diameter of the boss is generally less than the width of the tongue <NUM>, to allow more insulation between the boss and the edge of the tongue <NUM>.

In accordance with another feature not forming part of the invention, the tongue <NUM> and at least some of the receiver portion <NUM> of the terminal are covered with a layer of insulation material in the form of a coating for increasing the arc resistance of the terminal. (see <FIG>, for example) The layer of insulation material or coating is configured to cover a significant portion of the exposed terminal <NUM>, leaving only the respective bosses 220a, 220b exposed or free from the layer of insulation material for a suitable electrical connection through the terminal.

In one embodiment not forming part of the invention, the tongue <NUM> and part of the wire receiving portion <NUM> is covered with a layer or coating <NUM> made of a dielectric insulation material. In other embodiments, greater portions of the terminal have the insulation material coating layer formed thereon, and in some the entire terminal has the coating layer thereon. The coating of dielectric insulation material extends over the tongue, leaving only the respective bosses 220a, 220b free from the layer <NUM>.

The dielectric insulation material layer or coating <NUM> has desirable dielectric properties, and may include a material selected from one or more of the following: a fluorocarbon material (e.g., PTFE, PFA, FEP, ETFE, etc) a polymer material, PVC, polyurethane, a thermoplastic material, a phenolic material, silicone, rubber, a ceramic or some other material that provides dielectric protection, and/or sealing protection from fluid or vapor leakage as well as arc track protection along the insulation material surface or between conductive surfaces on and near the terminal. Also a combination of such materials might also be used for forming layer <NUM>. Referring to <FIG>, a layer <NUM> might also be formed by a chemical conversion process to form a conversion coating, as discussed herein.

The layer <NUM> is appropriately applied on at least a portion of the tongue <NUM>, and particularly, the entire tongue <NUM>, and also a portion of the wire receiving portion <NUM>, thus, leaving only the bosses 220a, 220b exposed. In one embodiment of the invention, a coating of dielectric material is applied to and formed on terminal <NUM> by an appropriate application process. The application process may include any appropriate process and might include a spray-on process, a dip process, or a mold process. An applied dielectric insulation material coating <NUM>, as illustrated in <FIG>, may have a thickness T of approximately <NUM> (<NUM>) inch to <NUM> inch (<NUM>).

In one embodiment not forming part of the of the invention, the dielectric insulation coating <NUM> may have a thickness T similar to the overall height H of the bosses. In that way, the coating in combination with the respective boss will provide or define the top face surface <NUM> and bottom face surface <NUM> of the tongue <NUM>.

In another embodiment not forming part of the invention the dielectric insulation coating <NUM> may have a thickness T that is less than the overall height H of the bosses.

In a more particular embodiment, as illustrated in the Figures, the coating <NUM> is dimensioned with a thickness T that is greater than the height H of the bosses 220a, 220b. In that way, as illustrated in <FIG>, <FIG>, <FIG> and discussed below, when the terminal <NUM> is secured to a terminal block or other connection point, and fastened down to contact the bosses, the coating <NUM> is slightly compressed down to the boss to seal the juncture at the bosses. By implementing an insulation material layer <NUM>, an environmental seal is created at the juncture of the tongue and a terminal block or other connection point. Furthermore, the seal reduces or eliminates a galvanic reaction of the dissimilar metal of the terminal and some other surface.

One possible material for the dielectric insulation material coating <NUM> is an RTV silicone rubber available from Nusil Technology LLC of Carpinteria, CA. A coating <NUM> may be sprayed onto the tongue <NUM> and surrounding area with the bosses <NUM> and aperture <NUM> appropriately masked or covered to keep a free electrically conductive surface. Alternatively, the coating <NUM> might be formed by dipping the tongue, again with the bosses and aperture covered. In still another alternative embodiment, a mold might be formed from the material that is then placed over or slid onto the tongue <NUM> to form coating <NUM>.

In one embodiment, as noted, the height H of the bosses 220a, 220b is dimensioned so as to be less than or below the thickness T of the dielectric insulation coating <NUM>. As illustrated in <FIG>, when terminal <NUM> is positioned such that the post <NUM> of terminal block <NUM> extends through aperture <NUM>, and the tongue <NUM> is fastened securely by an appropriate nut <NUM> and washer <NUM> (with a possible lock nut or lock washer, not shown) on post <NUM>, the bottom surface of the washer <NUM> and the surface <NUM> of the terminal block <NUM> each compress the insulation coating adjacent to the outer perimeter or edges of the respective bosses in order to make good electrical contact with the bosses and terminal tongue <NUM> while sealing the respective interfaces between the tongue <NUM> and nut <NUM>, and the tongue <NUM> and a conductive surface <NUM> of the terminal block <NUM>. In that way, the structures of the respective bosses are sealed. In accordance with one aspect of the invention, this keeps the metal of the tongue <NUM> and the bosses 220a and 220b from being a point of arc, such as between adjacent terminals on a terminal block, or with other metal structures adjacent to the tongue <NUM>.

The terminal not forming part of the invention was found to provide significant improvements in arc resistance when tested versus conventional terminals. More specifically, for testing the inventive terminal and cable assembly, a <NUM>% saline solution <NUM> was dripped onto a test arrangement <NUM>, as illustrated in <FIG>, wherein multiple cable assemblies <NUM> and terminals <NUM> were arranged next to each other on a terminal block <NUM>. Utilizing conventional terminals, arcing occurred with significant damage to the terminals and cable assemblies as rapidly as fifteen seconds and up to <NUM> minutes upon application of the test. Alternatively, implementing the arc resistant design of the present invention, arcing was prevented or delayed for as long as eight hours, with only minor damage to the tongues <NUM> of the terminals <NUM>. As such, the present invention provides a significant improvement over existing terminal equipment, and particularly over those arrangements which incorporate conventional cable assemblies and terminals connected very close together on a common terminal block.

Turning now to <FIG>, an alternative embodiment not forming part of the ef the invention is illustrated, wherein terminal 100a incorporates a non-conductive conversion coating layer that is formed on the tongue <NUM> by a chemical conversion process. Specifically, as illustrated in <FIG>, through a chemical conversion process, a significant Depth D of the metal of the terminal is converted to a conversion coating layer <NUM> that is generally electrically non-conductive. The conversion coating layer <NUM> is formed on the electrically conductive material of at least a portion of the tongue for reducing the conductivity of the tongue portion. For example, an anodizing process might be used to form layer <NUM>. Alternatively, another chemical conversion process might be used to form layer <NUM>. Specifically, in one embodiment, a layer <NUM>, such as an oxide layer, is formed on an aluminum terminal <NUM> through appropriate chemical conversion, such as by exposing the terminal <NUM> to an anodizing or chemical conversion process. In such a process, the bosses 220a and 220b and the aperture <NUM> are appropriately masked to prevent the conversion coating <NUM> from forming in that area so that the bosses and the aperture remain conductive for appropriate electrical coupling with a terminal bar, and threaded posts and nuts, as illustrated in <FIG>. Generally, a conversion coating might be formed to a Depth D of around <NUM>-<NUM> mils, although other depths might be suitable as well.

In accordance with still another embodiment not forming part of the present invention, as illustrated in <FIG>, an insulation material layer or coating <NUM> may be utilized in combination with a conversion coating layer <NUM> for the purposes of providing arc resistance in the terminal <NUM>. Referring now to <FIG>, a terminal 100b is illustrated that incorporates both the combination of a conversion coating layer <NUM> that is formed on terminal 100b, as well as an insulation material layer <NUM> that is applied on the terminal and over layer <NUM>. The combination of the two layers <NUM>, <NUM> provides additional arc resistance, with respect to terminal 100b. The insulation material layer <NUM> is formed to overlap at least a portion of the conversion coating layer <NUM>.

<FIG> illustrates another embodiment not forming part of the invention wherein a boss is located on only one side of the terminal tongue <NUM>. Specifically, it may only be necessary to secure the tongue to a conductive surface on one side and so a single boss, such as boss 220b as illustrated in <FIG> might be used. Boss 220b is located on a bottom side of the terminal <NUM> or tongue <NUM> so as to present a conductive surface to a conductive element or attachment point, such as terminal block <NUM> as shown in <FIG>. In the embodiment of <FIG>, the top surface of the tongue <NUM> is generally flat. Generally, it is desirable to utilize a boss where the tongue is attached to a surface so as to provide a desirable and consistent electrical connection at that point. As illustrated in <FIG> and <FIG>, it may be desirable to attach multiple terminals together when securing them to an attachment point, and so bosses 220a,b on both the top and bottom of the terminal <NUM> may be used as shown in <FIG>.

<FIG> illustrates a further embodiment not forming part of the invention. In several of the illustrated embodiments, the bosses 220a, b are illustrated as integral with or otherwise formed together with the structure of the tongue. In an alternative embodiment of terminal <NUM>, the boss 223a, b might be separately formed and then positioned around the aperture <NUM> of the tongue and used in conjunction with the tongue to realize the advantages of the invention. The bosses 223a, b would be similarly dimensioned and arranged and used as shown herein, in conjunction with a layer <NUM> or conversion coating layer <NUM> for realizing features and benefits of the invention.

With reference to <FIG>, the wire receiving portion <NUM> of the terminal <NUM> is configured to be crimped to form a cable assembly <NUM>, and has a continuous annular interior wall <NUM> forming a crimp portion <NUM> (<FIG>). In one embodiment of the invention, the crimp portion also seals the terminal in addition to making contact with conductor <NUM>, and thus, comprises a seal portion or sealing portion <NUM> and a wire contact portion <NUM>. The sealing portion <NUM> is adjacent to, and spaced from, the contact portion <NUM> toward aperture <NUM>. In one embodiment, a sealing portion surface <NUM> is broken into four areas 144a, b, c, d, as defined by three integral seal rings 146a, b, c protruding radially inward from the surface <NUM> as illustrated in <FIG>. In this embodiment the four areas 144a, b, c, d all measure substantially the same diameter, however in other embodiments the diameters may be different. Similarly, the seal rings 146a, b, c, having a smaller diameter than the diameter of the four areas 144a, b, c, d. The seal rings are illustrated with substantially the same diameter, however in other embodiments the diameters may be different. It is also contemplated that there may be more than or fewer than the three illustrated seal rings. A transition section <NUM> is positioned between the seal or sealing portion <NUM> and the contact portion <NUM>. The transition section <NUM> guides the conductor <NUM> of the wire <NUM> from the larger sealing portion <NUM> into the contact portion <NUM>, when the wire <NUM> is inserted into the terminal <NUM>. Suitable wire terminal crimp portion configurations for use with the present invention are disclosed in <CIT>, entitled "TERMINAL/CONNECTOR HAVING INTEGRAL OXIDE BREAKER ELEMENT", which Application is a Continuation-in-Part Application of <CIT>, entitled "TERMINAL/CONNECTOR HAVING INTEGRAL OXIDE BREAKER", now Issued <CIT>.

The terminal <NUM> of the invention may be used for forming a wire or cable assembly <NUM> (<FIG>), and the wire <NUM> is inserted in the terminal <NUM> so that the conductor <NUM> is guided by the section <NUM> into the contact portion <NUM>. The three seal rings 146a, b, c surround the insulation sheath <NUM>, and the contact portion <NUM> surrounds the conductor <NUM> of the wire. The assembly <NUM> is placed in a suitable crimping die, such as a modified hex crimping die, and crimped to make a cable <NUM> with a crimp <NUM>. The crimp <NUM> comprises <NUM> opposing concave facets <NUM> and four straight facets <NUM>. Between the facets are six corners <NUM>. On one of the concave facets <NUM> is an indicator button <NUM>. The indicator button <NUM> will be properly formed if the wire <NUM> was properly inserted and crimped.

Internally, as illustrated in <FIG>, the conductor <NUM> is squeezed together tightly at <NUM> in the sealing portion <NUM> and contact portion <NUM>, as compared to the portion <NUM> outside of the terminal <NUM>. The sealing rings 146a,b,c are squeezed into the insulating sheath <NUM> to make a hydrostatic seal <NUM>. The contact portion <NUM> is squeezed into the conductor <NUM> to give the assembly <NUM> a conductive electrical path <NUM> between the receiving portion <NUM> and the wire <NUM>.

In accordance with one embodiment, the sealing might be enhanced by implementing flexible seal rings along with the seal rings 146a - 146c. Specifically, as illustrated in <FIG>, one or more flexible seal rings 147a, 147b might be implemented in one or more of the areas 144a - 144d that are provided between the seal rings <NUM> of the sealing portion <NUM>.

For example, as illustrated in <FIG>, flexible seal ring 147a is positioned between and adjacent to rings 146a and 146b, while flexible seal ring 147b is positioned between and adjacent to rings 146b and 146c. The flexible seal rings <NUM> are formed of a suitably flexible material and are deposited in the appropriate spaces <NUM>, and would generally take up less than the space or volume between the seal rings <NUM>. Each of the flexible seal rings <NUM> is preferably formed continuously for <NUM>° around the surface of the sealing portion <NUM>. The flexible seal rings <NUM> are flexed when the wire receiving portion is crimped, as noted herein for forming a complete wire assembly or cable <NUM> using an appropriate wire.

Once the terminal <NUM> has been crimped to a wire, a suitable insulative sleeve might be placed over the crimp portion <NUM> and appropriately shrunk or secured over portion <NUM> and part of the wire <NUM>, as illustrated in <FIG> to further insulate the crimped metal of the terminal at the wire <NUM>.

<FIG> illustrate additional alternative embodiments not forming part of the invention incorporating the arc-resistant features of the invention. Specifically, those figures illustrate different terminal alternatives with the tongue having multiple apertures, having multiple bosses similar to those illustrated in <FIG>, or having a single elongated boss for multiple apertures. Furthermore, those embodiments illustrate various configurations involving insulation material layers. It should be readily understood that, for each of the embodiments as illustrated in <FIG>, different combinations of applied dielectric insulation material layers or coatings, conversion coating layers, and combinations thereof, might be utilized similar to the embodiments, as illustrated and described with respect to <FIG>. Therefore, while <FIG> and <FIG> illustrate just the use of an applied dielectric insulation material layer <NUM>, those embodiments could as well utilize only a conversion coating layer <NUM> as described or also might be implemented with a combination of both a conversion coating layer <NUM> and an insulation material layer coating <NUM> that is applied over the conversion coating layer.

Turning now to <FIG>, a terminal 100c is illustrated that has a tongue <NUM> having multiple apertures <NUM>. Each of the apertures has corresponding bosses 220a, 220b, as illustrated in <FIG> surrounding a respective aperture on a face surface of the tongue. The embodiment of <FIG> and <FIG> illustrate a material layer insulation <NUM> applied over the tongue <NUM> and over the transition area <NUM> transitioning into contact portion <NUM> of the wire receiving portion <NUM> of terminal 100c. As noted herein the bosses 220a, 220b will have a particular height H with respect to the face surfaces <NUM> and <NUM>, which is slightly less than the overall thickness T of the dielectric insulation material layer <NUM> for providing desirable sealing features, as noted herein.

To that end, <FIG> illustrates the terminal 100c as incorporated with a terminal block <NUM> having appropriate posts <NUM> and nuts <NUM> and washers <NUM> for physically and electrically coupling the terminal to the terminal block. As noted herein a lock washer (not illustrated) or a nut <NUM> with locking features might also be utilized with the nut <NUM> and washer <NUM> for providing a robust electrical and mechanical coupling of the terminal with a mounting or connection point or structure. Multiple apertures <NUM> provide multiple points of contact with terminal block <NUM> or some other connection point.

In accordance with one particular use not forming part of the invention, the raised bosses 220a, b provide a robust electrical connection on both sides of the terminal <NUM> when the terminal is connected to a connection point or to another terminal. Referring again to <FIG> and <FIG>, it provides an ability to stack multiple terminals together and one on top of each other for the purposes of securing the terminals to a connection point. The raised bosses 220a, b abut against each other as shown in the <FIG> for providing a robust electrical connection. For example, the topmost boss 220a of a terminal would abut with the bottommost boss 220b of another terminal that sits on top of the first terminal as illustrated. Both terminals may then be secured such as with an appropriate nut <NUM>, washer <NUM> (and any appropriate locking mechanism if desired). More than two terminals may be stacked as shown in <FIG>, <FIG> depending on the shape of the terminal and the orientation.

<FIG> illustrates another alternative embodiment not forming part of the invention, wherein terminal 100d is almost completely covered with the dielectric insulation material layer. Specifically, terminal 100d has multiple apertures <NUM> similar to the embodiment of <FIG>, and thus would be configured and would operate similarly to that embodiment, as illustrated in <FIG>. The dielectric insulation coating <NUM> is applied along the length of terminal 100d. Thus, the layer <NUM> extends beyond the transition portion <NUM> transitioning from the tongue <NUM>, up to the wire receiving portion <NUM>, and extends over the length of the wire receiving portion <NUM>, from the back face <NUM> out to the opening or aperture <NUM>, as discussed with respect to <FIG>. Accordingly, a greater portion of the exposed metal surfaces of the terminal 100d is covered with the dielectric insulation coating <NUM>. The elevated or raised bosses 220a, 220b are left uncoated, and are appropriately masked when material to form layer <NUM> is applied. <FIG> illustrates a cross-sectional view of terminal 100d of <FIG>.

In accordance with another embodiment not forming part of the invention, <FIG> and <FIG> illustrate an embodiment of the invention as terminal 100e, wherein an elongated boss spans between multiple apertures <NUM>. That is, for multiple apertures <NUM>, rather than individual single bosses, a single boss spans between the apertures <NUM> and surrounds both apertures. Specifically, an elongated upper boss 220d and elongated lower boss 220e each span between the apertures <NUM>. The bosses <NUM> d, e are free of the dielectric insulation material for the purposes of making electrical contact with an element, such as a conductive surface of a terminal block. As such, the bosses 220d, 220e are appropriately masked during the application of dielectric insulation material to form layer <NUM>. For electrical contact with terminal 100e, surfaces or connectors might be used in a terminal block that are shaped similarly to the bosses 220d, e for a robust electrical connection. <FIG> and <FIG> illustrate the dielectric insulation material layer <NUM> that extends the length of the tongue <NUM>, as well as the length of the wire receiving portion <NUM>. Alternatively, a layer <NUM>, which primarily covers mostly just the tongue <NUM>, might be implemented as illustrated in <FIG>. As such, in alternative embodiments, in combination with the conductive bosses, the layer <NUM> might not extend beyond the reference line <NUM>, as illustrated in <FIG>.

As discussed herein, the embodiments as illustrated in <FIG>, may incorporate various combinations of conversion coating layer and/or insulation material layers. Similar to the insulation material layer <NUM> as illustrated in <FIG>, the conversion coating layers might also extend only over the tongue, or over the entire terminal, including tongue <NUM> and the wire receiving portion of <NUM> or over the tongue <NUM> and a part of the wire receiving portion <NUM> of the terminal. Such conversion coating layers might also be utilized in combination with the insulation material layer <NUM> that is used predominantly over the tongue <NUM>, over the entire terminal or over the tongue and part of the terminal, as illustrated in <FIG>. Accordingly, embodiment not forming part of the invention is not limited to the specific embodiments only as shown in the figures, but may utilize various different combinations of the noted individual bosses 220a, 220b, and extended boss 220d, 220e, and/or the disclosed combinations of insulation material layers <NUM>, and conversion coating layers <NUM>.

Referring to <FIG>, the unique combination of the insulated coating and the exposed bosses provides suitable metal contact surfaces on the top and bottom of the tongue for the purposes of an electrical connection, while also reducing and/or preventing arc tracking, as well as accidental electrocution from exposure to the terminals.

<FIG>, <FIG> illustrate another possible feature that might be utilized with the various terminals not forming part of the present invention. Specifically, the inventive terminals might utilize a structure within the wire receiving portion <NUM> of the terminal, and particularly, in the contact portion <NUM>. To that end, the terminals might utilize an integral oxide breaker element for breaking through non-conductive oxide that may form on the surface of a conductor, such as an aluminum conductor.

The contact portion <NUM> has a continuous cylindrical wall <NUM> with a major diameter <NUM> and an integral oxide breaker or oxide breaker element <NUM>, the term this application will use for the macro object that breaks through the oxide layer on the conductor <NUM> when the wire receiving portion is crimped.

The integral oxide breaker element <NUM> comprises a plurality of protrusions, such as tapered protrusions <NUM>, extending radially inward from the major diameter <NUM> of the contact portion <NUM>. The protrusions are configured to engage the conductor of a wire positioned in the contact portion, and to protrude into the wire when the wire receiving portion is crimped. These tapered protrusions <NUM> may be separate from each other, but in other embodiments, for ease of manufacture, these tapered protrusions <NUM> are in the form of a helical thread <NUM> (<FIG>) that is conveniently manufactured on metal cutting or forming equipment. In one embodiment the thread <NUM> has a sixty degree included angle <NUM> and a pitch <NUM> of eighty, and is. <NUM> inch (<NUM>/<NUM>) deep. A pitch <NUM> of sixty has also worked successfully. It is contemplated that other included angles <NUM> and pitch <NUM> combinations as well as depths would also work. A minor diameter <NUM> of the threads equal to. <NUM> inch (<NUM>+/- <NUM>) has been used for wire gauge <NUM>/<NUM> (<NUM>). The oxide breaker <NUM> further comprises a coating <NUM> on the protrusions <NUM>. In various embodiments, the oxide breaker and the structures forming same might be coated with a material layer or left uncoated. In one particular embodiment, the coating <NUM> is an electroless nickel plate of. <NUM> per ASTM B733 Type III. This may be successfully put in the blind hole (blind refers to a hole with only one aperture <NUM>) by using an appropriate coating process. In addition to nickel, other coatings might be utilized and include electro nickel, gold, silver, tin and tin-lead, and alkaline-bismouth-tin.

The structure of the oxide breaker element provides not only the ability to break through the oxide layer on the conductor strand, but also improves the electrical and mechanical features of the invention. For example, electrically, the construction of the oxide breaker element increases the surface area of the crimp, and the contact with the conductor, to improve the overall electrical properties of the connection in the transition from the wire to the terminal. Furthermore, the oxide breaker element <NUM> increases the grip function at the contact portion <NUM>, and increases the pull force necessary to remove the wire <NUM> from terminal <NUM>.

It is also contemplated that other forms of structures or elements might be used for the oxide breaker element <NUM>, for example discrete annular protrusions might also be used. The making of one or more spiral threads is a widely perfected and efficient process. Other possible features and oxide breaker elements for use with the inventive terminals are discussed further in <CIT>, entitled "TERMINAL/CONNECTOR HAVING INTEGRAL OXIDE BREAKER ELEMENT", now <CIT> which Application is a Continuation-in-Part Application of <CIT>, entitled "TERMINAL/CONNECTOR HAVING INTEGRAL OXIDE BREAKER", now Issued <CIT>.

<FIG> disclose the arc resistant electrical terminal and grounding system of the invention. An attachable and readily detachable terminal is used with grounding structures as described herein to provide good electrical grounding or a power signal to a cable and greater flexibility in securing and reconfiguring the cables. Specifically, as illustrated in <FIG>, a terminal <NUM> includes a body made of a suitable electrically conductive material, such as copper or aluminum. As disclosed, the body of the terminal <NUM> has a suitable wire receiving portion <NUM> that may be appropriately crimped onto a wire or cable conductor. The wire receiving portion <NUM> may resemble structures as described herein with respect to <FIG>. The body also includes a cup portion <NUM> as shown in <FIG> and <FIG> that is electrically and physically coupled to the wire receiving portion <NUM> by a suitable connecting portion <NUM> (see <FIG>). The cup portion <NUM> interfaces with a post <NUM> and conductive structure <NUM> to secure the terminal end of a cable and ensure a proper ground or power signal reference.

The cup portion <NUM> further includes a boss portion <NUM> that extends downwardly from the bottom of the cup portion <NUM> as illustrated in <FIG>. In one embodiment, the boss portion is integrally formed with the cup portion <NUM>. The boss portion <NUM> makes electrical contact with a flat mounting surface <NUM> of the conductive structure <NUM>. The conductive structure <NUM> may provide a ground reference or a power signal and could be in the form of a bus bar, a mounting plate or block as appropriate to provide the electrical ground or power reference and structure for anchoring the end of a cable through the terminal <NUM>. To that end, the boss portion <NUM> has a complementary flat or planar surface <NUM> that interfaces with surface <NUM>.

In one embodiment of the invention as illustrated in <FIG>, <FIG>, <FIG>, a conductive stud or post <NUM> extends upwardly from the conductive structure <NUM> and is coupled thereto for securing the cup portion <NUM> of the terminal. In the embodiment of <FIG>, the post <NUM> is in the form of a bolt structure that fits through an aperture <NUM> in the conductive structure <NUM> as illustrated. The bolt has a head portion <NUM> that limits its passage through the aperture <NUM>. The post <NUM> includes threads <NUM> on an outer surface thereof for securing the terminal cup portion <NUM> as described herein. The post <NUM> may be a stainless steel structure and could have an outer coating or sheath of a more highly conductive metal, such as copper. The post may be secured with the conductive structure <NUM>, such as be soldering or otherwise affixing the post to the structure. In another embodiment as illustrated in <FIG>, the post 314a might be press fit or screwed into an appropriate feature 315a in the conductive structure <NUM>.

As shown in <FIG>, <FIG>, <FIG>, the body of terminal <NUM> includes an aperture <NUM> formed therein to extend through the cup portion <NUM> and boss portion <NUM>. The aperture may be appropriately sized for receiving the post <NUM> and allowing passage of the post <NUM> through the terminal boss portion and cup portion when the terminal <NUM> is mounted to conductive structure <NUM> and post <NUM>. That is, as shown in <FIG>, the post <NUM> extends upwardly through the boss portion <NUM> and the cup portion <NUM> through the aperture <NUM> and into the inside area <NUM> of the cup portion.

In order to secure the terminal <NUM> and specifically secure the boss portion <NUM> and cup portion <NUM> to conductive structure <NUM>, a fasterner <NUM> engages the post and secures the cup portion and surface <NUM> of the boss portion against the surface <NUM>. In one embodiment, the post <NUM> might include external threads <NUM>. Then, as illustrated in <FIG> and <FIG>, a fastener <NUM>, such as a threaded nut or other hardware fastener may be secured to the post <NUM> and tightened down to secure the cup portion <NUM> of terminal <NUM> against the conductive structure <NUM>. Specifically, the exposed surface <NUM> of the boss portion is secured tightly against the surface <NUM> of the conductive structure <NUM>. The fastener is configured to fit inside the area <NUM> of the cup portion to be contained therein. Although a single fastener <NUM> is shown in <FIG>, it would be understood that other hardware, such as washers, locking washers, and other structures might be utilized for securing terminal <NUM> to post <NUM> and mounting plate <NUM>. The fastener <NUM> is contained completely in the area <NUM> to be covered as described herein.

In accordance with one aspect of the invention, an overmold structure <NUM> of insulation material is formed on the cup portion. The overmold structure <NUM> covers the cup portion sides and the sides of the boss portion as seen in <FIG>. <FIG> illustrates the terminal <NUM> without the overmold structure, showing the cup portion and boss portion, as well as the connecting portion. The overmold structure is made of appropriate insulation material that is formed on the terminal <NUM> so that the side surface <NUM> of the cup portion and side surface <NUM> of the boss portion are appropriately covered with a layer of insulation material. The insulation material may include a suitable silicone material or one or more of the following: a fluorocarbon material, PTFE, PFA, FEP, ETFE, a polymer material, PVC, polyurethane, a thermoplastic material, a phenolic material, rubber, a ceramic. In one embodiment, the insulation material may be injection molded as an overmold structure <NUM> to cover various portions <NUM>, <NUM>, <NUM> of the terminal <NUM> for the prevention of arcing. The overmold structure might also extend over part of the wire receiving portion <NUM> as well. To that end, the terminal <NUM> as illustrated in <FIG> might include a feature, such as an indent <NUM>, that indicates the extend of the overmold structure <NUM> on the terminal. The overmold structure of insulation material <NUM> seals the electrical terminal <NUM> on the conductive structure <NUM> and electrically insulates the terminal <NUM>. The overmold structure <NUM> covers the side surfaces <NUM> and <NUM> and extends down the height H of the cup portion and boss portion but does not cover the bottom surface <NUM> of the boss portion <NUM>. The bottom surface <NUM> of the boss portion is exposed. In that way, insulation is provided between the cup portion <NUM> and connecting portion <NUM> with respect to the conductive structure, but a clear interface and conductive path is provided at the interfacing surfaces <NUM>, <NUM>. As shown in <FIG>, the cup portion <NUM> is mounted on post <NUM> so that the exposed bottom surface <NUM> of the boss portion <NUM> mounts flush against a top surface <NUM> of the conductive structure <NUM> while the overmold structure surrounds the sides of the cup portion and boss portion. Electrical current then flows through the conductive structure <NUM>, through the boss portion <NUM> and cup portion <NUM> and through the connecting portion <NUM> to wire receiving portion <NUM> and then to a wire, cable or other conductor that is crimped in portion <NUM>.

In accordance with one aspect the invention, the cup portion <NUM> and boss portion may have a combined height H that is dimensioned so as create the area <NUM> to contain most of the exposed post <NUM> and fastener <NUM> inside of the cup portion <NUM> of the terminal. In that way, all of the conductive hardware is covered with insulation material so as to prevent arcing. As illustrated in <FIG>, the top edge <NUM> and the inside surface <NUM> of the cup portion <NUM> that form the area <NUM> are exposed through the overmold structure <NUM> and the insulation material. The area <NUM> that is created within the insulated cup portion <NUM> by surface <NUM> completely surrounds and encapsulates the mounting post <NUM> and fastener <NUM>.

In accordance with one embodiment of the invention, to further enclose post <NUM> and conductive surfaces <NUM>, <NUM> of cup portion <NUM>, an insulating material cap <NUM> is secured into the top of the cup portion. The insulative cap <NUM> is configured for engaging the overmold structure <NUM> and sealing the cup structure around the post <NUM> of the conductive structure <NUM>. The insulative cap <NUM> fits over the opening of the cup portion <NUM> and area <NUM> and is dimensioned so as to overlie or overlap the overmold structure <NUM> proximate edge <NUM>. In that way, the entire internal surface <NUM> of the cup portion <NUM> that forms the area <NUM> containing the exposed section of post <NUM> as well as fastener <NUM> and any other mounting hardware are also completely enclosed with insulation material. The cap may have a portion <NUM> that engages the inside surface <NUM> of the cup portion and may be made of suitable material, such as PTFE or some other polymer or other material similar to the insulation material of the overmold structure. The insulating cap <NUM> may be secured in the cup portion <NUM> and overmold structure <NUM> by suitable securement methods. For example, a friction fit of section <NUM> with the inside surface <NUM> of the cup portion might be used. In another embodiment as shown in <FIG>, the portion <NUM> may include internal threads for threading onto the post <NUM> within the cup portion. Still other clip or lock structures might be used to allow the insulating cap <NUM> to be secured with the overmold structure to surround the terminal <NUM>.

For example, <FIG> illustrate possible embodiments wherein the cap <NUM> and the cup portion <NUM> are configured with complementary structures for a snap-in and lock engagement so the cap engages the overmold structure <NUM>. For example, referring to <FIG>, the cup portion <NUM> may include an indent <NUM> formed in a ring around the top edge <NUM> of the cup portion <NUM> that receives a similarly shaped or complementary shaped ridge feature <NUM> formed around the cap <NUM> for snapping the cap into position on the terminal <NUM>. Similarly, in <FIG>, an indent <NUM> formed in a ring around the cap <NUM> receives a similarly shaped or complementary shaped ridge feature <NUM> formed around the top edge <NUM> of the cup portion <NUM> of cap <NUM> for snapping the cap into position on the terminal <NUM> to engage the overmold structure <NUM> and seal the terminal.

In accordance with another feature of the invention, the terminal <NUM> can be readily removed by removing insulating cap <NUM> to expose the post <NUM>, fastener <NUM> or other hardware. The fastener(s) can be removed and the terminal <NUM> can then be readily slid from post <NUM>. Similarly, the terminal <NUM> may be re-applied or attached as disclosed herein. In that way, the terminal can be installed and is encapsulated in insulating material without having to apply such material in a separate step, such as in a coating step with tapes or epoxies. Furthermore, the hardware can be readily removed without having to clean off insulating material from the exposed surfaces. Still further, operator safety is improved, and arcing events are reduced because the hardware attachment elements, including the post <NUM> and fasteners <NUM>, are completely covered. As noted, the well or area <NUM> that is created within the insulated cup portion <NUM> completely surrounds and encapsulates the mounting post <NUM> and fastener <NUM>.

Claim 1:
An electrical terminal (<NUM>) for coupling to a conductive structure (<NUM>), the electrical terminal comprising:
a body having a wire receiving portion (<NUM>) for receiving a conductor;
a cup portion (<NUM>) electrically coupled with the wire receiving portion, the cup portion (<NUM>) defining an inside area (<NUM>) around the cup portion (<NUM>);
a boss portion (<NUM>) extending downwardly from a bottom of the cup portion (<NUM>) and including a planar surface (<NUM>) for interfacing with the conductive structure;
an aperture (<NUM>) formed in the body and extending through the cup portion (<NUM>) and the boss portion (<NUM>), the aperture configured to open into the cup portion (<NUM>) inside the area to receive a post (<NUM>) of the conductive structure and position a portion of the post (<NUM>) in the cup portion (<NUM>) inside area (<NUM>);
an overmold structure (<NUM>) of insulation material formed on the cup portion (<NUM>), the overmold structure (<NUM>) covering the cup portion (<NUM>) sides;
the boss portion (<NUM>) configured to surround the aperture at the bottom of the cup portion (<NUM>) for providing an electrically conductive surface free from insulation material for interfacing with the conductive structure;
a fastener (<NUM>) configured to fit inside of the cup portion (<NUM>) inside area (<NUM>) for engaging a post (<NUM>) and securing the cup portion (<NUM>) and boss portion (<NUM>) against the conductive structure;
an insulative cap (<NUM>) secured to the top of the cup portion (<NUM>), said insulative cap configured for engaging the overmold structure (<NUM>) and sealing the cup portion and its inside area (<NUM>) to seal the fastener (<NUM>) and the post (<NUM>).