Unique way of terminating devices using insulation displacement

Information

  • Patent Grant
  • 6674014
  • Patent Number
    6,674,014
  • Date Filed
    Friday, September 28, 2001
    22 years ago
  • Date Issued
    Tuesday, January 6, 2004
    20 years ago
Abstract
The present technique provides a technique for electrically wiring devices using insulation displacement. The technique arranges a plurality of insulation displacement members in wedge-shaped configurations for piercing an insulation layer and electrically contacting a conductor of an insulated electrical wire assembly. The insulation displacement members may be disposed at any suitable angles and offsets to provide an effective multipoint electrical contact with the conductor. The insulated electrical wire assembly also may be carried by a wire support structure to facilitate insertion and removal of the insulated electrical wire assembly with the arrangement of insulation displacement members.
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to the field of electronics, such as industrial automation, computing, network and communication devices. More particularly, the invention relates to a technique for electrically terminating devices using an assembly of wedge-shaped insulation displacement members, which are configured to pierce insulation and contact internal conductors.




Electrical devices are often inserted into electrical systems or networks in temporary or permanent configurations, which may require maintenance, replacement, swapping and other routine servicing. This routine servicing may require detachment and reattachment of the electrical device to the electrical system or network. Unfortunately, conventional wiring techniques typically involve fixed or single-use connection mechanisms, which are not particularly well suited for routine servicing or swapping of electrical devices within the electrical systems. For example, servicing or reconfiguration of the electrical system may require detachment and reattachment of a relay, a contactor, a push button, a terminal block or various other electrical devices.




Accordingly, there is a present need for an improved technique for wiring to electrical devices, such as relays, contactors, pushbuttons, and terminal blocks. There is a particular need for a quick and efficient wiring technique, which facilitates connectivity to a plurality of devices without rewiring of each device.




SUMMARY OF THE INVENTION




The present invention provides a novel technique for electrically wiring devices, such as industrial automation, computing, network and communication devices and various systems of such devices. The technique arranges a plurality of insulation displacement members in wedge-shaped configurations for piercing an insulation layer and electrically contacting a conductor of an insulated electrical wire assembly. The insulation displacement members may be disposed at any suitable angles and offsets to provide an effective multipoint electrical contact with the conductor. The insulated electrical wire assembly also may be carried by a wire support structure to facilitate insertion and removal of the insulated electrical wire assembly with the arrangement of insulation displacement members. The foregoing technique is applicable in a wide range of electronic devices and systems. However, it is particularly well suited for electronic devices requiring maintenance, servicing, replacement, swapping and other routine access or removal. For example, the present technique may be applied to components suitable in several applications or locations within a network.




In one aspect, the present technique provides an electrical connector comprising a first insulation displacement member disposed at a first angle and a second insulation displacement member disposed at a second angle. The first and second insulation displacement members also comprise conductive blades configured for contacting a conductor disposed in an insulative material.




In another aspect, the present technique provides an electrical wiring system. The system comprises a plurality of insulation displacement members disposed at desired angles for electrically contacting an insulated electrical wire assembly. An electrical connector is also coupled to the plurality of insulation displacement members for electrically coupling the insulated electrical wire assembly to a desired device.




In another aspect, the present technique provides a method of coupling an insulated electrical wire assembly to a desired device. The method comprises angularly piercing insulation of the insulated electrical wire assembly in a plurality of locations. The insulated electrically wire assembly is also electrically contacted in the plurality of locations.




In another aspect, the present technique provides a method of forming an electrical connector for coupling an insulated electrical wire assembly to a desired device. The method comprises providing a plurality of electrical connector members comprising wedge-shaped cutting members. The method also includes disposing the plurality of electrical connector members in desired angles relative to an axis extending through the wedge-shaped cutting members.











BRIEF DESCRIPTION OF THE DRAWINGS




The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:





FIG. 1

is a perspective view of an exemplary wiring system of the present technique;





FIG. 2

is a top view of the wiring system illustrating connectivity of wires with an exemplary electrical contactor;





FIG. 3

is a perspective view of the electrical contactor;





FIG. 4

is an exploded view of the electrical contactor; and





FIG. 5

is an exploded view of the wiring system illustrating an alternate configuration of the electrical contactor.











DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS




Turning now to the drawings, and referring first to

FIG. 1

, an electrical system is illustrated in accordance with the present technique and designated generally by reference numeral


10


. The electrical system


10


may include a variety of insulated electrical wire assemblies and components, such as relays, contactors, pushbuttons, terminal blocks, circuits, and other desired electric, electronic and computing components. For example, the electrical system


10


may be incorporated into any desired electrical system or network, including networks of manufacturing and assembly devices, communication devices, electrical transmission and control devices, computing devices, any various other industrial devices. As illustrated, the electrical system


10


includes an electrical contact section


12


disposed on an electrical device


14


, and a wire carrier section


16


disposed on an electrical device


18


. These electrical contact and wire carrier sections


12


and


16


facilitate an efficient electrical contact between the electrical devices


14


and


18


. Moreover, these sections


12


and


16


may be incorporated into one or more mobile or stationary devices, such as devices usable in mobile systems, devices swappable for multiple uses, devices removable or swappable with fixed devices, devices fixed in a network or electronic system, or any other suitable applications, as described above.




The electrical contact section


12


comprises one or more electrical contactors configured to pierce insulation of an insulated wire assembly and electrically contact a conductor disposed within the insulated wire assembly. For example, the electrical contact section


12


illustrated in

FIG. 1

has an electrical contactor


20


disposed in locations


22


,


24


,


26


and


28


along a wiring side


30


of the electrical device


14


. Each of these electrical contactors


20


is configured for electrically contacting one or more insulated wires carried by the wire carrier section


16


of the electrical device


18


. For example, the wire carrier section


16


illustrated in

FIG. 1

has receptacle sets


32


,


34


,


36


and


38


configured to support insulated wire sets for insertion into the electrical contactors


20


disposed in locations


22


,


24


,


26


and


28


, respectively. These receptacle sets


32


,


34


,


36


and


38


may embody closed receptacles, open receptacles, closeable receptacles, or any other suitable wire support structure. Also note that the receptacle sets


32


,


34


,


36


and


38


are disposed in a staggered configuration to facilitate a smooth intercoupling of the insulated wires with the contactors


20


disposed in the electrical device


14


. As the electrical devices


14


and


18


are interlocked, this staggered configuration reduces the overall force required to insert the insulated wires into the contactors


20


. Accordingly, any suitable staggering may be used to reduce the insertion force of the insulated wires. As illustrated, the electrical device


18


has an insulated wire set


40


extending through the receptacle set


38


. This insulated wire set


40


, and any other insulated wire sets disposed in the receptacle sets


32


,


34


,


36


and


38


, may embody any number, gauge, geometry, grouping or configuration of insulated wire assemblies. However, in this exemplary embodiment, the receptacle set


38


and the corresponding electrical contactor


20


are configured to support and contact insulated wire assemblies


42


and


44


, which have insulation layers


46


and


48


disposed about conductors


50


and


52


, respectively. Any suitable insulation and conductor material may be used within the scope of the present technique.




As the electrical device


18


is moved toward the wiring side


30


, the insulated wire assemblies


42


and


44


are inserted into receptacles


54


and


56


, where the electrical contactor


20


pierces the insulation layers


46


and


48


and electrically contacts the conductors


50


and


52


, respectively. The electrical device


18


also has a connector assembly


58


for mechanically coupling the electrical device


18


to the electrical device


14


at the wiring side


30


. In this exemplary embodiment, the connector assembly


58


comprises a pair of snap members


60


for tool-lessly coupling the electrical device


18


to the wiring side


30


. The electrical device


14


also may have a plurality of the electrical contact sections


12


, each of which is configured to receive insulated wire sets directly or carried by a wire carrier section. As illustrated, the electrical device


14


has an electrical device


62


coupled to the wiring side


30


adjacent the electrical contact section


12


for the electrical device


18


. Accordingly, the electrical device


14


may have one or more separate or integrated electrical or electronic components disposed within its housing


64


, as discussed above. The electrical device


14


also may have an insulated wire assembly


66


for coupling the electrical device


14


to a desired electric, electronic or computing system or network.




The operation of the electrical contactor


20


is best illustrated with reference to

FIGS. 1 through 3

.

FIG. 2

is a top view of the electrical contact section


12


illustrated in

FIG. 1

, while

FIG. 3

is a perspective view of the electrical contactor


20


. As discussed above, insulated wire assemblies may be inserted directly into the contactors


20


or they may be carried and supported by the electrical device


18


. For illustrative purposes in

FIG. 2

, the insulated wire assemblies


42


and


44


are inserted into the receptacles


54


and


56


of the contactor


20


without the structure of the electrical device


18


. In each of the receptacles


54


and


56


, the contactor


20


includes a plurality of blades for cutting through insulation and electrically contacting the internal conductor.




The plurality of blades may be configured in any suitable configuration and orientation. For example, the contactor


20


has blade pairs


68


and


70


disposed in the receptacle


54


at angles


72


and


74


, respectively, for piercing the insulation layer


46


and electrically contacting the conductor


50


of the insulated wire assembly


42


. The contactor


20


also has blade pairs


76


and


78


disposed in the receptacle


56


at angles


80


and


82


, respectively, for piercing the insulation layer


48


and electrically contacting the conductor


52


of the insulated wire assembly


44


. The foregoing angles


72


,


74


,


80


and


82


may comprise any suitable angle for cutting through the insulation layers


46


and


48


and to provide a reliable electrical contact with the conductors


50


and


52


. For example, the blade pairs


68


,


70


,


76


and


78


may be disposed at the same or different angles of 30°, 45°, 60°, 90° or any other oblique angle. Moreover, the blade pairs


68


,


70


,


76


and


78


may be disposed in parallel (i.e., the same angle), in a staggered orientation for contacting the insulated electrical wire assemblies in multiple longitudinal positions, in a converging configuration (e.g., inwardly toward one another or toward a common point), in a symmetrical or non-symmetrical orientation relative to the insulated wire assemblies


42


and


44


, or any other suitable orientation between the respective blade pairs.




As illustrated in

FIG. 3

, the blade pairs


68


,


70


,


76


and


78


also have a generally wedge-shaped configuration to facilitate cutting through the insulation and securement of the wires within the contactor


20


. For example, the wedge-shaped configuration may embody a V-shaped, U-shaped, or Y-shaped wire opening between the respective blade pairs. The blade pairs also may be disposed in sets along one or more shared planes, such as illustrated in FIG.


3


. As illustrated, the blade pairs


68


and


78


and the blade pairs


70


and


76


share common planes and define W-shaped wire openings for the insulated wire assemblies


42


and


44


, respectively. Moreover, The blade pairs


68


,


70


,


76


and


78


also may comprise any suitable material for piercing, electrically contacting, and retaining the respective wire assemblies. For example, the blade pairs


68


-


78


may embody a metallic structure, an insulative structure having one or more metallic blades, and insulative structure having one or more electrical contacts, or any other suitable configuration.




The contactor


20


also may have one or more retaining structures for securing the insulated wire assemblies


42


and


44


within the receptacles


54


and


56


, respectively. For example, the contactor


20


has a pair of wedge shaped structures


84


disposed on opposite ends of the receptacle


54


, while a pair of wedge shaped structures


86


are disposed on opposite ends of the receptacle


56


. The foregoing wedge shaped structures


84


and


86


are configured to provide a compressive force on the insulation layers


46


and


48


to retain the insulated wire assemblies


42


and


44


within the receptacles


54


and


56


, respectively. The wedge shaped structures


84


and


86


also may have a texture, a blade, or any other structure to provide a frictional force against the insulation layers.




The electrical contactor


20


may be formed from a variety of materials and components, including insulative and conductive materials, blade structures, retention structures, electrical housings, wiring and circuitry, and various other features. For example, the electrical contactor


20


may comprise an insulative housing


88


(e.g., an electrical housing) and insulation displacement assemblies


90


and


92


, as illustrated by the exploded view of FIG.


4


. In this exemplary embodiment, the insulation displacement assembly


90


is insertable into a slot


94


, which extends through a side slot


96


, a center slot


98


, and a side slot


100


of the insulative housing


88


. Either before or after insertion of the insulation displacement assembly


90


into the slot


94


, the insulation displacement assemblies


90


and


92


may be coupled together via slots


102


and


104


, respectively. The insulation displacement assembly


92


is also insertable into a slot


106


, which extends through a side slot


108


, the center slot


98


, and a side slot


110


of the insulative housing


88


.




In this exemplary embodiment, the insulation displacement assemblies


90


and


92


are disposed in an X-shaped or crisscross configuration, wherein the blade pairs


68


,


70


,


76


and


78


all converge at the center slot


98


of the insulative housing


88


. In this X-shaped configuration, the insulation displacement assemblies


90


and


92


may be configured symmetrically or non-symmetrically. For example, the insulation displacement members


90


and


92


may be disposed perpendicular to one another and symmetrical relative to the receptacles


54


and


56


. Alternatively, the insulation displacement assemblies


90


and


92


and the respective blade pairs may be disposed in parallel, in a staggered orientation in equal or different angles, or any other desired angular orientations. The electrical contactor


20


also may have a plurality of the insulation displacement assemblies


90


and


92


configured in the X-shaped configuration or any other desired orientation. As described above with reference to

FIG. 3

, the blade pairs


70


and


76


and the blade pairs


68


and


78


are each disposed on common planes via the insulation displacement assemblies


90


and


92


, whereon the blade pairs form W-shaped receptacles for cutting through wire insulation, contacting the conductor, and retaining the both of the insulated wire assemblies


42


and


44


. It also should be noted that each of the insulation displacement assemblies


90


and


92


may embody insulative structures having separate metallic/conductive blades for each of the blade pairs


70


and


76


and


68


and


78


, respectively.




As described above, the electrical contact section


12


facilitates efficient electrical wiring for the electrical system


10


. The present technique also facilitates efficient detachment of the electrical devices


14


and


18


. Although insulated wire sets may be directly inserted into the receptacles


54


and


56


of the electrical contactor


20


, the wire carrier section


16


facilitates efficient electrical wiring, removal, swapping and servicing of the electrical devices


14


and


18


. For example, the wire carrier section


16


illustrated in

FIG. 1

facilitates simultaneous coupling and uncoupling of four separate insulated wire sets, while the respective insulated wire sets are continually supported and retained by the wire carrier section


16


. Accordingly, the electrical device


18


may be quickly uncoupled from the electrical device


14


and then recoupled to any other desired electrical device without rewiring the electrical device


18


.




As mentioned above, the electrical devices


14


and


18


may embody any desired circuitry, switches, electronics and structures, which may be intercoupled via the foregoing sections


12


and


16


. For example, in an exemplary embodiment of the system


10


, the electrical device


14


may embody a coil or other energizable magnetic section, a contactor section disposed adjacent the coil, and circuitry to energize the coil and thereby magnetically move the contactor section to a desired electrical connection position. For example, the coil may cause prongs of the contactor section to close an electrical path between the insulated wire assembly


66


and one or more of the contactors


20


in the electrical contact section


12


. If the electrical device


18


is coupled to the electrical device


14


, then the foregoing magnetically induced closure may provide a desired connection between the insulated wire assemblies


42


and


44


and the insulated wire assembly


66


.




It also should be noted that the electrical contact and wire carrier sections


12


and


16


may be integrated into a single electrical device, such as the electrical devices


14


or


18


, which may be configured for a mobile or stationary application. In this alternate configuration, an electrical plug may be provided for electrical coupling with another device. This electrical plug may have a snap-fit mechanism or any other suitable connection mechanism for fixedly or removably coupling the electrical devices. For example, an alternate embodiment of the electrical system


10


is illustrated in

FIG. 5

, wherein the electrical contact and wire carrier sections


12


and


16


are both disposed in the electrical device


18


. In this exemplary embodiment, the electrical device


62


may have the electrical contact and wire carrier sections


12


and


16


disposed separately or integrally together in the electrical devices


14


and


62


, respectively. Accordingly, one of the electrical devices


18


and


62


may be configured as illustrated in

FIG. 1

, while the other may be configured as illustrated in FIG.


5


.




As illustrated, the electrical device


18


has the wire set


40


extending through the receptacle set


38


of the wire carrier section


16


, which supports the insulated wire assemblies


42


and


44


for electrical coupling with the electrical contact section


12


. In this exemplary embodiment, the electrical contact section


12


has contactors


20


disposed adjacent the receptacle sets


32


,


34


,


36


and


38


in positions


112


,


114


,


116


and


118


within the electrical device


18


, respectively. The electrical device


18


also has an electrical coupling assembly


120


for electrically intercoupling the electrical devices


14


and


18


. This electrical coupling assembly


120


may embody any suitable electrical connection mechanism, such as an electrical plug, rigid electrical contactors, insulated wire assemblies, or other such electrical connectors. As illustrated, the electrical coupling assembly


120


comprises electrical connectors


122


,


124


,


126


and


128


, which are electrically coupled to the contactors


20


disposed in positions


112


,


114


,


116


and


118


, respectively.




Accordingly, a desired electrical connection can be achieved by inserting an insulated wire set through a desired receptacle set in the wire carrier section


16


, moving and inserting the insulated wire set into the contactor


20


disposed adjacent the desired receptacle set, and then interlocking the electrical device


18


and the corresponding electrical coupling assembly


120


with the electrical device


14


and a corresponding mating electrical coupling assembly. The electrical devices


14


and


18


are mechanically interlocked via the connector assembly


58


, as described in FIG.


1


. As the electrical devices


14


and


18


are interlocked, the insulated wire sets disposed in the respective receptacle sets


32


,


34


,


36


and


38


and contactors


20


of the electrical device


18


are secured or biased into the respective contactors (i.e., in positions


114


,


116


,


118


and


120


) via a contact retention assembly


130


, which is disposed in the electrical device


14


. In this exemplary embodiment, the contact retention assembly comprises tab pairs


132


,


134


,


136


and


138


, which are configured to bias the insulated wire assemblies into the receptacles


54


and


56


of the contactors


20


at positions


114


,


116


,


118


and


120


, respectively. In operation, the insulated wire sets may simply be positioned over the respective contactors


20


, and then, as the electrical devices


14


and


18


are interlocked, the respective tab pairs would bias the insulated wire sets into the contactors


20


to make an electrical connection. In either case, the integral arrangement of the electrical contact and wire carrier sections


12


and


16


in the electrical device


18


facilitates efficient device swapping, insertion and removal without repetitively rewiring the devices.




While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown in the drawings and have been described in detail herein by way of example only. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.



Claims
  • 1. An electrical connector, comprising:a first insulation displacement member disposed at a first angle; and a second insulation displacement member disposed at a second angle; wherein the first and second insulation displacement members comprise conductive blades configured for slideably contacting a conductor disposed in an insulative material by a progressive wedging and cutting motion.
  • 2. The electrical connector of claim 1, wherein the first and second insulation displacement members are staggered along a longitudinal axis for the conductor.
  • 3. The electrical connector of claim 2, wherein the first and second angles are different oblique angles.
  • 4. The electrical connector of claim 3, wherein the first and second insulation displacement members are angled inwardly toward one another.
  • 5. The electrical connector of claim 2, wherein the conductive blades are disposed in a wedge-shaped configuration for receiving the conductor disposed in the insulative material.
  • 6. The electrical connector of claim 5, comprising a retention structure for securing the conductor.
  • 7. The electrical connector of claim 6, wherein the retention structure comprises a wedge-shaped receptacle configured to provide a compressive force on the insulative material.
  • 8. The electrical connector of claim 1, wherein a plurality of first and second insulation displacement members are disposed in an electrical connector housing for electrical coupling with an insulated electrical wire assembly comprising a plurality of the conductor.
  • 9. The electrical connector of claim 8, wherein the plurality of first insulation displacement members are position along a first plane at the first angle, and the plurality of second insulation displacement members are positioned along a second plane at the second angle.
  • 10. An electrical connector, comprising:a plurality of insulation piercing members disposed at a plurality of axial locations and angular positions relative to an axis, wherein the insulation piercing members have progressive sideways edges to cut sideways along and to pierce into an insulated conductor; and a conductive member disposed in each of the plurality of insulation displacement members.
  • 11. The electrical connector of claim 10, wherein the plurality of insulation piercing members comprise wedge-shaped structures within the connector receptacle.
  • 12. The electrical connector of claim 10, wherein the plurality of insulation piercing members comprise V-shaped structures within the connector receptacle.
  • 13. The electrical connector of claim 10, wherein the plurality of insulation piercing members comprise W-shaped structures within the connector receptacle.
  • 14. The electrical connector of claim 10, wherein the plurality of insulation piercing members comprise X-shaped structures within the connector receptacle.
  • 15. The electrical connector of claim 10, wherein at least two of the angular positions are substantially symmetrical relative to the axis.
  • 16. The electrical connector of claim 10, wherein at least two of the angular positions are substantially parallel relative to the axis.
  • 17. The electrical connector of claim 10, wherein at least one of the angular positions has an oblique angular orientation relative to the axis.
  • 18. The electrical connector of claim 10, wherein at least one of the conductive members comprises a cutting blade.
  • 19. The electrical connector of claim 10, wherein at least one of the conductive members is coupled to an electrical connector lead.
  • 20. The electrical connector of claim 10, wherein at least two of the conductive members are coupled together.
  • 21. The electrical connector of claim 10, wherein at least two members of the plurality of insulation piercing members are disposed in staggered positions along the axis.
  • 22. The electrical connector of claim 10, wherein the at least two members are disposed in different oblique angles relative to the axis.
  • 23. An electrical connector, comprising:a crosswise-receiving receptacle for an insulated conductor; a plurality of insulation displacement structures fixedly extending into the crosswise-receiving receptacle at different longitudinal positions along the crosswise-receiving receptacle, wherein the insulation displacement structures comprise sideways and inward cutting edges.
  • 24. The electrical connector of claim 23, wherein the crosswise-receiving receptacle has a lengthwise opening for a length of the insulated conductor.
  • 25. The electrical connector of claim 23, comprising a plurality of the crosswise-receiving receptacle.
  • 26. The electrical connector of claim 23, wherein the plurality of insulation displacement structures comprise conductive members.
  • 27. The electrical connector of claim 26, wherein the conductive members comprise cutting structures.
  • 28. The electrical connector of claim 26, wherein the conductive members comprise electrical connector leads.
  • 29. The electrical connector of claim 23, wherein the plurality of insulation displacement structures comprise wedge-shaped structures.
  • 30. The electrical connector of claim 23, wherein the plurality of insulation displacement structures comprise V-shaped structures.
  • 31. The electrical connector of claim 23, wherein the plurality of insulation displacement structures comprise W-shaped structures.
  • 32. The electrical connector of claim 23, wherein the plurality of insulation displacement structures comprise X-shaped structures.
  • 33. The electrical connector of claim 23, wherein at least two of the plurality of insulation displacement structures are oriented in different angles relative to a longitudinal axis of the crosswise-receiving receptacle.
  • 34. The electrical connector of claim 33, wherein the different angles comprise oblique angles relative to the longitudinal axis.
  • 35. The electrical connector of claim 23, wherein at least two of the plurality of insulation displacement structures are oriented in substantially symmetrical angles relative to a longitudinal axis of the crosswise-receiving receptacle.
  • 36. The electrical connector of claim 23, wherein at least two of the plurality of insulation displacement structures are oriented in substantially parallel angles relative to a longitudinal axis of the crosswise-receiving receptacle.
  • 37. An electrical connector, comprising: receptacle means for receiving a length of an insulated conductor having an insulation layer surrounding an internal conductor; and multi-point contacting means disposed in the receptacle means for slideably cutting along and progressively piercing into the insulation layer and electrically contacting the internal conductor at multiple contact orientations.
  • 38. The electrical connector of claim 37, comprising a plurality of the receptacle means having the multi-point contacting means.
  • 39. The electrical connector of claim 37, comprising retaining means for securing the insulated conductor within the receptacle means.
  • 40. The electrical connector of claim 37, wherein the multi-point contacting means are disposed in V-shaped configurations.
  • 41. The electrical connector of claim 37, wherein the multi-point contacting means are disposed in W-shaped configurations.
  • 42. The electrical connector of claim 37, wherein the multi-point contacting means are disposed in longitudinally-staggered positions relative to the receptacle means.
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