Information
-
Patent Grant
-
6674014
-
Patent Number
6,674,014
-
Date Filed
Friday, September 28, 200123 years ago
-
Date Issued
Tuesday, January 6, 200421 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Reichard; Dean A.
- Lee; Jinhee
Agents
- Swanson; Tait R.
- Gerasimow; Alexander M.
- Walbrun; William R.
-
CPC
-
US Classifications
Field of Search
US
- 439 418
- 439 413
- 439 409
- 439 389
- 439 395
- 439 396
- 439 405
- 439 439
- 174 176
-
International Classifications
-
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.
US Referenced Citations (7)