Frame assembly

A frame assembly for mounting an insulation displacement connector block includes a base frame and a modular subframe attached to the base frame. The subframe is capable of being attached to the base frame in a first position or a second position, which are generally perpendicular to each other.

FIELD

The present invention relates to an electrical connector assembly. More particularly, the present invention relates to a frame assembly for mounting an electrical connector block, such as an insulation displacement connector block (“connector block”), where the frame assembly includes a base frame and a modular subframe.

BACKGROUND

In a telecommunications context, electrical connector blocks are connected to cables that feed subscribers while other electrical connector blocks are connected to cables that are fed from a processing center. To make the electrical connection between the subscriber block and the processing center block, a jumper wire (e.g., an electrical conductor) may be inserted in the electrical connector block to complete the electrical circuit. Typically a jumper wire can be connected, disconnected, and reconnected several times as the consumer's needs change.

A connector block including an insulation displacement connector (“IDC”) is a useful type of electrical connector because electrical connections may be made without having to strip an insulated conductor of its insulation. An IDC element within the connector block cuts through the insulation, thereby making an electrical connection with a conductive core of the conductor.

When a connector block is used in the telecommunications context, the connector block is typically mounted in a central location, such as a telecommunications closet, an outdoor cabinet, an aerial terminal or closure or other common use applications along with a plurality of other connector blocks. Specifically, the connector block is attached to a frame, and the frame is attached to the central location. A telecommunications worker may need to access the connector block in the central location in order to make the necessary electrical connections between subscriber blocks and processing center blocks, or between other devices.

BRIEF SUMMARY

In a first aspect, the present invention is a frame assembly for mounting an insulation displacement connector block. The frame assembly comprises a first base frame and a first subframe capable of receiving the insulation displacement connector block. The first subframe is attached to the first base frame. The first subframe is capable of being attached to the first base frame in a first position or a second position, where the first position and the second position are generally perpendicular to each other.

In a second aspect, the present invention is a frame assembly comprising a base frame and a first modular subframe attached to the base frame. The base frame includes a generally planar sidewall. The first modular subframe includes a first longitudinal edge, and is capable of receiving an insulation displacement connector block. The first subframe is capable of being attached to the base frame in a first position or a second position, where in the first position, the first longitudinal edge is generally parallel to the sidewall of the base frame, and in the second position, the first longitudinal edge is generally perpendicular to the sidewall of the base frame.

In a third aspect, the present invention is a frame assembly for mounting a plurality of insulation displacing connector blocks. The frame assembly comprises a base frame having a generally square inner perimeter, and a plurality of modular subframes attached to the inner perimeter of the base frame. The plurality of modular subframes are generally parallel to each other. Each modular subframe is detachable from the base frame, and each modular subframe is capable of receiving at least one of the plurality of insulation displacement connector blocks.

The above summary is not intended to describe each disclosed embodiment or every implementation of the present invention. The figures and the detailed description which follow more particularly exemplify illustrative embodiments.

While the above-identified figures set forth exemplary embodiments of the present invention, other embodiments are also within the invention. In all cases, this disclosure presents the invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope and spirit of the principles of the invention.

DETAILED DESCRIPTION

The present invention is a frame assembly for mounting a connector block, where the frame assembly includes a base frame and a subframe. The subframe, which is capable of receiving at least one connector block, is capable of attaching to the base frame in at least two positions. In the description of the present invention, two positions are described—a first position and a second position. In one embodiment, the first position and second position are generally perpendicular to each other. The dual positioning may enable the frame assembly to be used to mount the connector block so that its housings are aligned in a generally horizontal orientation (the first position) or aligned in a generally vertically stacked orientation (the second position). The generally horizontal and vertical orientations of a connector block are described in U.S. patent application Ser. No. 11/131,639, entitled, “ELECTRICAL CONNECTOR ASSEMBLY AND METHOD OF FORMING THE SAME,” which was filed on the same date as the present application.

The frame assembly of the present invention may be used to mount a connector block in a central location. For example, the frame assembly may be attached to a frame panel in a telecommunications closet. The frame assembly is used to mount a plurality of connector blocks in the central location.

In one embodiment, the frame assembly includes a plurality of subframes. In this embodiment, the subframes used in the frame assembly of the present invention are modular. The modularity is two-fold. First, the subframes have standardized dimensions so that they are substantially similar in size. Second, the subframes may be flexibly arranged on the base frame. The subframes may be attached to the base frame in at least two positions. This will be discussed in reference toFIGS. 1-5below.

The frame assembly of the present invention is versatile because each subframe may be individually detached and reattached to the base frame. As a result, a connector block, which is attached to a subframe, may be removed from the base frame and/or replaced.

A connector block may become damaged some time after it is mounted in a central location. Depending upon the needs of the particular telecommunications network, space within the central location may be at a premium. A damaged connector block may be an inefficient use of space, and it may be desirable to replace the damaged connector block with an undamaged one. In existing frame assemblies, it is difficult to replace a connector block that is mounted in the central location because the connector block may be permanently affixed to the frame. It is even more difficult to replace a single connector block at a time. In existing frame assemblies, the frame is typically a single piece. In order to replace a connector block (whether it is damaged or otherwise), the entire frame must be removed from the central location and replaced, thereby wasting the undamaged connector blocks that may also be attached to the replaced frame and requiring additional labor for disconnecting and reconnecting conductors to the undamaged connector blocks.

In the present invention, a connector block is not permanently affixed to the base frame because the connector block is attached to a subframe and the subframe may be detached from and reattached to the base frame, or a new subframe may replace a removed subframe. In alternate embodiments, the connector block may be permanently attached to the subframe, or it may also be detachable therefrom. If the connector block becomes damaged, the subframe, and thus the damaged connector block, may be removed from the base frame. A subframe having an undamaged connector block may then be attached to the base frame in the gap created by the removal of the damaged connector block and its respective subframe. If the damaged connector block is permanently attached to its subframe, a new subframe (and undamaged connector block) may be attached to the base frame; if the damaged connector block is not permanently attached to its subframe (the “old” subframe), the damaged connector block may be removed from the old subframe and an undamaged connector block may be attached to the old subframe, and the old subframe may be reattached to the base frame.

One or more subframes may be attached to the base frame. In this way, the base frame can be used to mount more than one connector block. Because the present invention allows a damaged connector block to be removed from the base frame, the entire base frame does not need to be replaced when there is a damaged connector block. Undamaged connector blocks that are also attached to the base frame may remain on the base frame. Of course, the entire base frame may be replaced if the need arises. The present invention provides an efficient means of mounting a connector block because the entire frame assembly does not have to be replaced if a single connector block is damaged.

FIG. 1is an exploded perspective view of an exemplary embodiment of frame assembly10of the present invention, which includes base frame12and modular subframes14,16,18,20, and22. InFIGS. 1,3A, and3B, the subframes14,16,18,20, and22, when assembled, attach to base frame12in a first position. A second position is described in reference toFIGS. 4 and 5. As discussed above, modular subframes14,16,18,20, and22of the present invention allow frame assembly10to have subframes14,16,18,20, and22arranged in at least two positions. These positions are described as a first position and a second position. The designation of the two positions in the exemplary embodiment as a “first” position and a “second” position are for clarity of description, and is not intended to limit the present invention in any way. Rather, the “first position” and “second position” designations below may also be swapped, so that the “first position” described in reference toFIG. 1is called the “second position” and the “second position” described in reference toFIGS. 4 and 5is called the “first position”.

Subframes14,16,18,20, and22are each configured to receive a connector block (e.g., connector block42inFIG. 3B). Although the exemplary embodiment shows frame assembly10with five subframes14,16,18,20, and22, a frame assembly in accordance with the present invention may have any suitable number of subframes. The features of each one of subframes14will be described in reference to subframe22. However, in the exemplary embodiment, subframes14,16,18,20, and22are modular. That is, subframes14,16,18,20, and22have standardized dimensions so that they are substantially similar in size. Because of the modularity, the description of subframe22is representative of each subframe14,16,18,20, and22.

Base frame12includes first sidewall12A, second sidewall12B, third sidewall12C, and fourth sidewall12D. First sidewall12A is generally parallel to second sidewall12B, and third sidewall12C is generally parallel to fourth sidewall12D. First and second sidewalls12A and12B are generally perpendicular to third and fourth sidewalls12C and12D. Preferably, sidewalls12A,12B,12C, and12D together form an inner perimeter of base frame12, which preferably has a generally square shape.

The generally square shape allows the same number of subframes (such as give subframes14,16,18,20, and22) to be attached to base frame12in two positions, where the two positions are generally perpendicular to each other. The two positions are illustrated inFIGS. 1,3A, and3B (first position), andFIGS. 4 and 5(second position). In the first position, first end14A of subframe14is adjacent first sidewall12A of base frame12, and second end14B of subframe is adjacent second sidewall12B of base frame12; first end16A of subframe16is adjacent first sidewall12A of base frame12, and second end16B of subframe16is adjacent second sidewall12B of base frame12, and so forth with respect to subframes18,20, and22. The second position will be described in reference toFIGS. 4 and 5.

Of course, if base frame12did not have a generally square inner perimeter, subframes14,16,18,20, and22may still be attached to base frame12in two generally perpendicular positions. For example, subframes14,16,18,20, and22may have an adjustable length, or a different number of subframes in the first position than in the second positions (e.g., 5 subframes in first position and 8 subframes in the second position). Taking subframe22as exemplary of subframes14,16,18, and20, a distance between first end22A and second end22B of subframe22may be adjustable so that the length L of subframe22may be varied, which may allow subframe22to extend from one sidewall to another for various distances between sidewalls.

In the embodiment shown inFIG. 1, subframe22attaches to base frame12using a latch mechanism. Projection24fits within a recess in base frame12. The recess mechanically engages with projection24so that subframe22is securely attached to base frame12. The recess that corresponds with projection24of first end22A of subframe22is not in view inFIG. 1. However, similar-shaped recesses26are seen inFIG. 1. Each sidewall12A,12B,12C, and12D of base frame12has a plurality of recesses26about the inner perimeter of base frame12. Each of the recesses26are configured to receive a projection (e.g., projection24) of subframes14,16,18,20, and22. In the exemplary embodiment ofFIG. 1, two projections24are on opposite ends22A and22B of subframe22, and each projection24fits within a separate recess in base frame12. For each subframe, the two recesses that correspond to each projection24on the subframe are on opposite sidewalls of the base frame12. For example, in the first position of subframe22inFIG. 1, a projection24on first end22A of subframe22fits within recess (not shown inFIG. 1) on first sidewall12A of base frame12, and a projection24on second end22B of subframe22fits within a recess26A on second sidewall12B of base frame.

The latch mechanism allows subframes14,16,18,20, and22to each be selectively removed from base frame12without substantial damage to either part. In order to release the latching mechanism to remove subframe22from base frame12, projections24on first end22A and second end22A of subframe22may be pressed inward, towards the center of subframe22, thereby releasing each projection24from its respective recess26, and at nearly the same time, subframe may be lifted from base frame12.

Any other suitable means or mechanism for attaching subframes14,16,18,20, and22to base frame12may also be used. For example, an adhesive or another type of mechanical “mating” system may be used. In an exemplary embodiment, the attaching means or mechanism chosen allows each subframe14,16,18,20, and22to be removed from base frame12. In another exemplary embodiment, the attaching means or mechanism chosen does not substantially damage base frame12when subframe14,16,18,20, and/or22is removed from base frame12, so that a replacement subframe may be placed where the removed subframe was attached to base frame12. In another exemplary embodiment, the attaching means or mechanism chosen does not substantially damage the subframe upon removal so it may be reattached. The latching mechanism in the exemplary embodiment allows for both a relative release of subframe22from base frame12with little to no damage to base frame12.

Subframe22further includes ribs27A and27B. Ribs27A and27B are used interlock subframe22with base frame12, and to position subframe22with respect to base frame12. Specifically, each rib27A and27B mates with their respective grooves29in base frame12so that the direction subframe22attaches to base frame12within the first position (and the second position) is predetermined and preset. In the first position, the end of rib27A near the first end22A of subframe22fits within groove29A (shown inFIG. 2A) on first sidewall12A of base frame12; the end of rib27A near the second end22B of subframe22fits within groove29B on second sidewall12B of base frame12; and the end of rib27B near the second end22B of subframe22fits within groove29C on second sidewall12B.

In an exemplary embodiment ribs27A and27B are different lengths. Rib27A is longer than rib27B, where the length is measured along the same direction as length L of subframe22, so that rib27A mates with grooves on both first and second sidewalls12A and12B, respectively, while rib27B mates with grooves only on second sidewall12B. The different length ribs27A and27B makes it difficult for subframe22to fit within base frame12in a direction opposite to that shown inFIGS. 1 and 3A, where first end22A of subframe22is adjacent first sidewall12A. There is only one groove29A on first sidewall12A that corresponds to rib27A. If subframe22was rotated 180 degrees, rib27B would not have a groove to mate with on first sidewall12A.

Base frame12further includes a plurality of grooves29arranged about the inner perimeter of base frame12so that ribs27of each subframe14,16,18,20, and22may mate with their respective grooves. Grooves29for each subframe14,16,1820, and22are arranged similarly to grooves29A,29B, and29C so that within a subframe position, each subframe14,16,18,20, and22fits within base frame12in the same direction (i.e., so that first end14A,16A,18A,20A, and22A are all adjacent the same sidewall12A,12B,12C, or12D). Ribs27and grooves29also help to ensure that, within the first position, the connector blocks attached to each subframe14,16,18,20, and22are arranged in the same direction. Subframes14,16,18,20, and22and their respective connector blocks may be configured so that the connector block can only fit onto its respective subframe in one direction.

In some embodiments, it may be beneficial to have subframes14,16,18,20, and22attached to base frame12in the same direction because there may also be the most clearance between connector blocks when subframes14,16,18,20, and22are attached to base frame12in the same direction. The clearance between the connector blocks may facilitate access to the housings of the connector blocks.

Of course, in alternate embodiments, subframes14,16,18,20, and22may be configured to attach to base frame12in either direction. For example, first end14A of subframe14may be adjacent first sidewall12A, while first end16A of subframe16may be adjacent first sidewall12A.

Subframe22includes arms28, which extend from subframe22and are preferably integral with subframe22. A connector block may be attached to subframe22using arms28. Arms28mechanically engage with a slot (e.g., slot42A inFIG. 3B) in a connector block (e.g., connector block42inFIG. 3B), thereby attaching the connector block to subframe22. The mechanical engagement between arms28and the connector block may be permanent, or in an alternate embodiment, the connector block may be removed from arms28without substantial damage to subframe22or connector block42. Arms28and the respective slots of the connector block may be configured so that the connector block attaches to subframe22in only one direction. Each subframe14,16,18,20, and22includes similar arms28, so that each subframe14,16,18,20, and22is configured to receive a connector block. The present invention also contemplates any other suitable means of configuring each subframe14,16,18,20, and22to receive a connector block. For example, another mechanically engaging mechanism may be used, or the connector block and subframe may be adhered together using an adhesive.

Base frame12includes tabs30, which extend from first sidewall12A, and tabs32, which extend from second sidewall12B. Each subframe14,16,18,20, and22of frame assembly10is capable of receiving at least one electrical connector. A plurality of conductors may be connected to each electrical connector. Tabs30and32may be used to manage the plurality of conductors that may be attached to the plurality of connector blocks that are attached to frame assembly10(by subframes14,16,18,20, and22). One end of a conductor is typically connected to a connector block; thereafter, the conductor may be routed through an opening (i.e., openings40inFIG. 2B) created between adjacent tabs30and first sidewall12A and between adjacent tabs32and second sidewall12B, thus separating the plurality of conductors, which may be connected to the connector blocks that are attached to the frame assembly, into groups. Labels may be placed on each one of tabs30and32to identify the conductors that are being fed through each corresponding opening. If a telecommunications worker needs to disconnect a conductor from a connector block, tabs30and32may allow the worker to easily identify the location of the conductor. Furthermore, the openings (i.e., openings40inFIG. 2B) may help to prevent the conductors from becoming tangled.

FIG. 2Ais a top view of base frame12ofFIG. 1, and illustrates how tabs30and32may extend from base frame12. Tabs30extend from first sidewall12A by way of arms30A, and tabs32extend from second sidewall12B by way of arms32A.FIG. 2Aalso shows screw holes34. A screw (or other suitable mechanism) may be inserted in each screw hole34to mount base frame12in the central location.

Base frame12is typically mounted on a generally vertical surface so first and second sidewalls12A and12B extend in a generally vertical direction (e.g., in a z-coordinate direction, where orthogonal x-z coordinates are shown inFIG. 2A, and where a y-coordinate direction runs perpendicular to the plane of the image), and third and fourth sidewalls12C and12D extend in a generally horizontal direction (e.g., in a x-coordinate direction). Further, when base frame12is mounted in the central location, tabs30and32are preferably aligned in the generally vertical direction so that tabs30does not share x-coordinates with tabs32, and so that each one of tabs30have the same x-coordinate, and each one of tabs32have the same x-coordinate.

Also shown inFIG. 2Ais notch36and indentation38on base frame12. Notch36is formed so that it may interconnect with a indentation of an adjacent base frame (which may also be mounted in the central location), where the indentation has generally the same shape as indentation38. Indentation38is formed so that it may interconnect with a notch of an adjacent base frame, where the notch has generally the same shape as notch36. When base frame12is mounted in the central location with a plurality of other base frames, notch36and indentation38allow base frame12to fit together with adjacent base frames.

FIG. 2Bis a side view of base frame12, and shows how tabs30, together with first sidewall12A, form a plurality of openings40for receiving one or more conductors that are connected to a connector block that is mounted on frame assembly10. Arms30A are somewhat flexible so that a conductor may be introduced through gap40A between tabs30in order to reach the respective opening40. However, arms30A should also be somewhat rigid so that when the conductor is introduced through gap40A, the conductor does not incidentally exit its respective opening40. A telecommunications worker who wishes to remove the conductor from its respective opening may do so, though, because of the somewhat flexible arms30A. Although it is not seen in the view shown inFIG. 2, tabs32, which extend from second sidewall12B, also form a plurality of openings for receiving a conductor. Tabs32and their respective openings are “behind” tabs30and openings40in the plane of the image ofFIG. 2B.

FIG. 3Ais a perspective view of frame assembly10ofFIG. 1as assembled. Subframes14,16,18,20, and22are attached (or “mounted”) to base frame12so that they are generally parallel to each other, and so that subframe14is positioned between subframe16and third sidewall12C of base frame12, subframe16is positioned between subframes14and18, subframe18is positioned between subframes16and20, subframe20is positioned between subframes18and22, and subframe22is positioned between subframe18and fourth sidewall12D (not shown inFIG. 3). When a connector block is attached to each subframe14,16,18,20, and22, and the subframes are attached to base frame12as shown inFIG. 3, the connector blocks are also generally parallel to each other and adjacent one another. Because of this close arrangement of connector blocks, the cable management features of tabs30and32may be beneficial. If each connector block is capable of receiving twenty conductors, and there are five connector blocks on frame assembly10, up to 100 conductors would be in a small amount of space at a time. Tabs30and32may be used to arrange the conductors in an organized fashion.

The number of connector blocks that may be mounted on a frame assembly of the present invention varies depending on many factors, including the dimensional parameters of the central location in which the frame assembly is expected to be mounted (which in turn, may depend on the needs of the particular telecommunications network the central location serves to connect).

FIG. 3Bis the assembled perspective view of frame assembly10, where a connector block42is attached to subframe22. Arms28of subframe22extend through slot42A on opposite ends of connector block42and mechanically engage therewith. In this way, connector block42is attached to subframe22, and thereby attached to base frame12. As previously stated, in alternate embodiments of the present invention, an alternate method of attaching subframe22and connector block42may be used. Furthermore, the attachment may be permanent or semi-permanent (where connector block42may be removed from subframe22if necessary, but is still securely attached to subframe22).

The depiction of connector block42inFIG. 3Bis for clarity of illustration and is merely used as an aid to describe the present invention. The present invention may be used with any suitable type of connector blocks, not only a connector block that resembles connector block42shown inFIG. 3B. Examples of suitable connector blocks that may be used in accordance with the present invention are described in U.S. patent application Ser. No. 10/941,506, entitled, “INSULATION-DISPLACEMENT SYSTEM FOR TWO ELECTRICAL CONNECTORS”, and filed on Sep. 15, 2004, and U.S. patent application Ser. No. 10/941,441, entitled, “CONNECTOR ASSEMBLY FOR HOUSING INSULATION DISPLACEMENT ELEMENTS”, and filed on Sep. 15, 2004.

FIG. 4is an exploded perspective view of frame assembly11, which is frame assembly10ofFIG. 2, where subframes14,16,18,20, and22are positioned to attach to base frame12in the second position. In the second position, first end14A of subframe14is adjacent third sidewall12C of base frame12, and second end14B of subframe is adjacent fourth sidewall12D of base frame12; first end16A of subframe16is adjacent third sidewall12C of base frame12, and second end16B of subframe16is adjacent fourth sidewall12D of base frame12, and so forth with respect to subframes18,20, and22.

In the second position, the end of rib27A near the first end22A of subframe22mates with groove29D on third sidewall12C, and the end of rib27A near the second end22B of subframe22mates with groove29E on fourth sidewall12D. The end of rib27B near the second end22B of subframe22mates with grooves29F on fourth sidewall12D. Ribs27of each subframes14,16,18, and22similarly fit within grooves29along third sidewall12C and fourth sidewall12D. Ribs27and grooves29help to ensure that within the second position, each subframe14,16,18,20, and22fits within base frame12in the same direction (i.e., so that first end14A,16A,18A,20A, and22A are all adjacent third sidewall12C).

Frame assembly11may be mounted in a central location in the same way as frame assembly10, so that first and second sidewalls12A and12B of base frame12extend in a generally vertical direction, while third and fourth sidewalls12C and12D extend in a generally horizontal direction. As a result of subframes14,16,18,20, and22each being in its second position, the connector block that is attached to each subframe14,16,18,20, and22is mounted in the central location in a generally “vertical” position. Each connector block typically includes a plurality of housings, and in the second position, those housings are in a vertically stacked orientation. If a connector block has a greater dimension in its length than width, the connector block may be described as being mounted in the second position so that its lengths are each elongated in the vertical direction.

Tabs30and32of base frame12may also be used for cable management purposes with frame assembly11.

In an exemplary embodiment of the present invention, subframes14,16,18,20, and22each attach to base frame12using a latching mechanism (described above). Because base frame12includes a plurality of recesses26arranged about all four sidewalls12A,12B,12C, and12D (along the inner perimeter of base frame12), subframes14,16,18,20, and22may be attached to base frame12in either the first position (frame assembly10ofFIGS. 1 and 3) or the second position (frame assembly11ofFIGS. 4 and 5). A telecommunications worker may move subframes14,16,18,20, and22between the first position and the second position in the field. Specifically, subframes14,16,18,20, and22may be detached from base frame12and reattached to base frame12in another position.

FIG. 5is an assembled perspective view of frame assembly11ofFIG. 4, where subframes14,16,18,20, and22are each attached to base frame12in the second position. As previously stated, in the second position, each subframe14,16,18,20, and22is attached to base frame12so that it generally perpendicular to its positioning in the first position. Subframes14,16,18,20, and22are attached (or “mounted”) to base frame12so that they are generally parallel to each other, and so that subframe14is positioned between subframe16and first sidewall12A of base frame12, subframe16is positioned between subframes14and18, subframe18is positioned between subframes16and20, subframe20is positioned between subframes18and22, and subframe22is positioned between subframe18and second sidewall12B (not shown inFIG. 5).

Materials for the frame and subframe may be selected to provide desirable characteristics such as strength durability, resilience, cost, and ease of manufacture. Exemplary materials include acetal, polybutylene terephthalate, polyester, polyamide, polyetherketone, and metals such as aluminum and steel. These may be injection molded or stamped and formed as appropriate for the selected material.

While a “horizontally” mounted connector block (i.e., the first position of frame assembly10) is the conventional way of mounting a connector block at the time the present application is filed, there are advantages to “vertically” mounted connector blocks (i.e., the second position of frame assembly11). These advantages are described in U.S. patent application Ser. No. 11/131,639entitled, “ELECTRICAL CONNECTOR ASSEMBLY AND METHOD OF FORMING THE SAME,” and filed on the same date as the present application. A frame assembly in accordance with the present invention may be mounted in a central location so that the subframes are in a first position, and connector blocks are “horizontally” mounted. However, the subframes may later be arranged to be in a second position, in order for the connector blocks to be “vertically”mounted. This later arrangement may be made in the field. The present invention is versatile because of the modularity of the subframes and adaptability of the frame assembly to different subframe (and therefore, connector block) positions.

Although the present invention is only described with respect to the telecommunications industry, other applications of a frame assembly in accordance with the present invention are contemplated. Likewise, although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.