Information
-
Patent Grant
-
6530808
-
Patent Number
6,530,808
-
Date Filed
Tuesday, October 17, 200024 years ago
-
Date Issued
Tuesday, March 11, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Bradley; P. Austin
- Gushi; Ross
Agents
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
An electrical connector member for a coaxial cable. The connector member comprises a first section and a second section. The first section has two or more portals therein, each portal adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of an electrical contact in the member. The second section includes a conductor receiving section of the electrical contact, the conductor receiving section having a diameter adapted to receive a center conductor of the cable. Each crimp area is located on the conductor receiving section, wherein an electrical connection is formed by crimping the electrical contact to the conductor at each crimp area using the indentors. The crimped connection provides a substantially matched impedance in that section of the connector.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to RF coaxial cable connectors and more particularly to a coaxial cable connector having improved voltage standing wave ratio through minimal impedance mismatch.
2. Brief Description of Earlier Developments
In most coaxial connector designs, it is a common practice to either crimp or solder the center conductor of the cable before assembling the center contact inside the connector. Crimping the center contact is a desirable termination method due to the lower applied cost of the cable assembly. Examples of crimping an electrical terminal to an exposed end of an inner conductor of a coaxial cable can be found in U.S. Pat. Nos. 5,273,458 and 5,490,801. In these cases, the center contact of the connector is terminated to the coaxial cable conductor via a crimping tool before assembly within the outer conductor and the dielectric member. However, in connector designs that incorporate a center contact pre-assembled with the remainder of the connector, termination must be made through portals in the outer conductor shell of the assembly. Termination of the center conductor of the coaxial cable in these designs can also be either crimp or solder. Methods of crimping through portals are described in U.S. Pat. Nos. 3,297,978, 4,047,788, 4,096,627. However, portal style crimps described to date have worse RF performance levels, due to the impedance mismatch effects of the portals. U.S. Pat. Nos. 3,297,978; 4,047,788; 4,096,627 describe the crimping of the center contact of the connector through opposed crimp portals, but fail to address the resulting electrical effects of the crimped connector. With the increased need for higher frequency ranges to support for example the expanding wireless communications markets, RF connectors used in telecommunication systems are required to operate at higher frequency ranges and with lower losses to make these systems function at their peak performance. Therefore, it would be desirable to be able to connect a coaxial cable conductor to a conductor receiving member via portals in the outer conductor shell of the connector, while at the same time optimizing the impedance of the connector as well as enhancing the overall RF performance of the connector, which are results not achieved or realized using any of the conventional connectors.
SUMMARY OF THE INVENTION
The present invention is directed to in a first aspect, an electrical connector member for a coaxial cable. In one embodiment, the connector member comprises a first section and a second section. The first section has two or more portals therein, each portal adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of an electrical contact in the member. The second section includes a conductor receiving section of the electrical contact, the conductor receiving section having a diameter adapted to receive a center conductor of the cable. Each crimp area is located on the conductor receiving section, wherein an electrical connection is formed by crimping the electrical contact to the conductor at each crimp area using the indentors. The crimped connection provides a substantially matched impedance in that section of the connector.
In another aspect, the present invention is directed to an electrical connector member for a coaxial cable. In one embodiment, the member comprises a first section having four portals and a second section including a conductor receiving section of an electrical contact in an interior section of the connector. Each portal is adapted to align a corresponding indentor of a crimping tool over a predetermined crimp area on the electrical contact. Each indentor is aligned adjacent to its respective portal as the connector member is inserted into the positioner of the crimping tool. The conductor receiving section has a diameter adapted to accommodate a center conductor of the cable. Preferably, the contact is adapted to be assembled in the connector member before a crimping operation. In the preferred embodiment, the crimp on each crimp area forms an electrical connection between the contact and the conductor and provides a substantially matched impedance for the crimp section of the connector.
In another aspect, the present invention is directed to a method of making a crimp-style coaxial electrical connector assembly having a generally uniform impedance. In one embodiment, the method comprises providing a coaxial electrical connector having an inner conductor, an outer conductor and a dielectric element separating the inner and outer conductor. A coaxial cable with a center conductor is provided and the inner conductor is engaged with the center conductor. The inner conductor is crimped to the center conductor through at least two openings in the outer conductor. The crimping step creates an area of impedance mismatch on the connector that is compensated for to provide the generally uniform impedance across the connector.
In a further aspect, the present invention is directed to a coaxial electrical connector with an inner conductor crimped to a center conductor of a coaxial cable through an outer conductor. In one embodiment, the improvement comprises the outer conductor having an inner diameter selected to compensate for an impedance mismatch created by the crimp, so that the connector has a generally uniform impedance thereacross.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing aspects and other features of the present invention are explained in the following description, taken in connection with the accompanying drawings, wherein:
FIG. 1
is an exploded, perspective view of a connector sub-assembly incorporating features of the present invention.
FIG. 2
is an elevational view of a portion of the connector sub-assembly shown in
FIG. 1
for purposes of highlighting the dimensions of a portal.
FIG. 3
is a cross-sectional view of the connector sub-assembly taken along line III—III in FIG.
5
.
FIG. 4
is a cross-sectional view of the front end of the connector sub-assembly of
FIG. 1
taken along the line A—A before the crimping step.
FIG. 5
is a partial cross-sectional view of the connector sub-assembly of
FIG. 1
taken along the line A—A before the crimping step.
FIG. 6
is a cross-sectional view of an assembled (i.e. after the crimping step) connector sub-assembly incorporating features of the present invention.
FIG. 7
is a cross-sectional view of a mated connector assembly incorporating features of the present invention on both connectors.
FIG. 8
is an exploded, perspective view of a crimping tool assembly incorporating features of the present invention.
FIG. 9
is a partial cross-sectional view of the locator portion of the crimping tool assembly of
FIG. 8
taken along the line z—z.
FIG. 10
is an elevational view of the components of a connector sub-assembly of the present invention partially inserted into the crimp tool.
FIG. 11
is an elevational view of a connector sub-assembly of the present invention fully inserted into the crimp tool, but before the crimping step, including a partial cross-sectional view of the locator portion of the positioner and the crimp tool.
FIG. 12
is a perspective view of one embodiment of a connector sub-assembly incorporating features of the present invention inserted into a positioner device and before the indentors enter the portals for crimping.
FIG. 13
is a cross-sectional view of a connector sub-assembly fully inserted into the crimp tool during the crimping step, i.e. showing the indenters crimping the contact to the conductor.
FIGS. 14 and 15
are graphical representations of test data for a connector sub-assembly incorporating features of the present invention.
FIGS. 16 and 17
are graphical representations of test data for a connector sub-assembly incorporating a solder termination of the coaxial conductor.
FIG. 18
is an exploded, perspective view of a connector sub-assembly of the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to
FIG. 1
, there is shown an exploded perspective view of a connector sub-assembly
6
incorporating features of the present invention. Although the present invention will be described with reference to the single embodiment shown in the drawings, it should be understood that the present invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials could be used.
In one embodiment, the connector
6
can be made from multiple machined pieces. Generally, the front end
48
and the back end
60
are adapted to be mechanically and electrically coupled together. Referring to
FIGS. 1
,
5
and
6
, the flange
144
can seat circumferentially against a complimentary portion
96
of the back end
60
. In one embodiment, the front end
48
and back end
60
may be coupled together by soft soldering the sub-assemblies together. In an alternate embodiment, the front end
48
and the back end
60
may be coupled together using any suitable electrical and mechanical connection method or device. In an alternate embodiment, the connector
6
can be manufactured as a one-piece connector. The front end
48
can include a pin or socket assembly adapted for mating with a complimentary connector assembly. The back end
60
can include two or more portals
68
, and a hollow bore
58
that is adapted to receive a coaxial cable.
The connector
6
is adapted to allow the center conductor of the coaxial cable to be connected, both electrically and mechanically, to a conductor receiving member
26
of the connector
6
, the connection optimizing the impedance of the connector as well as the RF performance of the connector. In this embodiment, the conductor receiving member
26
can be crimped to the center contact of the coaxial cable. It is a feature of the present invention to provide an improved mechanism and method of crimping a contact to a conductor through a portal.
As shown in
FIGS. 1
,
5
and
6
, the connector
6
can include two or more portals
68
extending through the back end
60
of the connector
6
into a hollow section or bore
56
. Each portal
68
provides access for insertion of an indentor
102
of a crimping tool
130
as shown in
FIGS. 8 and 12
. The design of each portal
68
is such that a subsequent crimp exerted by the crimping tool places a crimp
22
in a precise location on the conductor receiving member
26
as shown in FIG.
6
. It is a feature of the present invention that by locating a crimp in a precise location on the conductor receiving member
26
, by selecting the dimensions of the outer shell and each portal, and by using a crimp ferrule, that the impedance of the connector is optimized and the overall RF performance of the connector
6
is enhanced. These are significant improvements and enhancements that are not realized in any prior portal connector design.
As shown in
FIGS. 1 and 6
, connector
6
comprises plug (male) connector. Alternatively, the connector
6
may also take the form of an electrical receptacle (female) connector that is adapted to mate with the plug connector
6
of
FIG. 1
, as depicted in FIG.
7
. Once cables
38
are secured thereto, plug connector
6
A and receptacle connector
6
B are secured within a housing R and housing H, respectively as shown in FIG.
7
. Plug connector
6
A mounts to motherboard MB and receptacle connector
6
B mounts to daughter card DC.
The connector
6
can include a hollow bore
58
at one end of the back end
60
. The hollow bore
58
is generally adapted to be inserted between certain layers of a coaxial cable as described below. As shown in
FIG. 6
, a coaxial cable generally has an outer layer or jacket
40
covering an electrically conducting shielding layer
42
, which in turn covers a dielectric or insulation layer
44
. In the central portion of the cable
38
, and covered by the dielectric layer
44
, is an electrically conducting center conductor
46
. In one embodiment, the coaxial cable
38
can be 26 AWG coaxial cable, such as for example ALPHA WIRE CO. P/N 9316, M17/113-RG316. However, in alternate embodiments, the coaxial cable
38
can be any suitable cable for high frequency communication applications.
The bore
58
extends between the dielectric layer
44
and the shielding layer/cable braid
42
. Referring to
FIG. 5
, an inner diameter Ø
1
of the hollow bore
58
is generally sized just large enough to accommodate a center conductor
46
and a dielectric layer
44
of a coaxial cable
38
. In one embodiment, the inner diameter Ø
1
of the hollow bore
58
can be approximately 0.063 inches (1.600 millimeters) in order to accommodate a coaxial cable having a dielectric diameter of approximately 0.060 inches (1.524 millimeters). In an alternate embodiment, the inner diameter Ø
1
of the hollow bore
58
can be sized to any suitable dimension in order to accommodate a desired coaxial cable
38
. The knurled exterior surface
82
of back end
60
abuts cable braid/shielding layer
42
.
Referring to
FIGS. 1 and 5
, in one embodiment, the back end
60
of the connector
6
can include a tapered diameter
66
. The tapered diameter
66
can be approximately between the section
64
of back end
60
that includes the portals
68
and the section
62
that includes the hollow bore
58
. As shown in
FIGS. 1
,
5
and
6
, an outer surface of the section
62
can include a conductive crimping surface
82
over which the conductive shielding layer
42
of the cable
38
can be secured. In one embodiment, the crimping surface
82
can comprise a knurled surface. Once bore
58
is inserted between insulation layer
44
and shielding layer
42
of cable
38
, a crimp ferrule
80
can be positioned over the back end
60
of connector
6
in order to secure the shield layer
42
positively to the connector
6
. In an alternate embodiment, any suitable surface and manner of connection can be used to establish a mechanically and electrically secure conductive bond between the connector
6
and the shield layer
42
.
The crimp ferrule
80
generally comprises a conductive member adapted to secure, both mechanically and electrically, the cable
38
and the shield layer
42
to the connector
6
. Referring to
FIG. 6
, in this embodiment, the crimp ferrule
80
covers the portals
68
and provides shielding effectiveness against radio frequency (“RF”) leakage.
Referring to
FIGS. 1
,
5
and
6
, the connector
6
may also include a chamfered edge
78
along the leading edge of back end
60
near hollow bore
58
where the cable
38
is inserted. The chamfered edge
78
can be used to separate the shield layer
42
from the dielectric layer
44
upon insertion of the coaxial cable
38
into the connector
6
.
In one embodiment, the connector
6
is symmetrical and can include four portals
68
, also referred to as portholes, each portal
68
being spaced around a circumference of the back end
60
of connector
6
at approximately 90° from an adjacent portal. In an alternate embodiment, the connector
6
can include any suitable number of portals
68
. Referring to
FIG. 2
, each portal
68
generally has a length L
1
greater than its width W
3
. In one embodiment, the length L
1
of a portal
68
can be approximately 0.1700 inches (4.318 millimeters) while the width W
3
of a portal
68
can be approximately 0.0650 inches (1.651 millimeters). In an alternate embodiment, the length and width of a portal
68
can be any suitable dimension. Referring to
FIG. 12
, the size of the portals
68
closely mirrors the size of the indenters
102
in the crimping tool
130
in order to guide the indenters
102
into the connector
6
and to an aligned position. In the aligned position, each indentor
102
is adapted to apply a crimp
22
in a predetermined location on the conductor receiving member
26
as shown in FIG.
6
. The design of each portal
68
, including its length, width and position, are generally adapted to optimize the impedance of the connector and to enhance its overall RF performance. The crimp tool will be described in more detail below.
Generally, as shown in
FIG. 3
, the back end
60
of the connector
6
has an interior section
56
. The inner diameter of interior section
56
is identified as Ø
2
. Back end
60
also includes two or more portals
68
, with a width identified as W
3
. Centrally interposed within section
56
is the conductor receiving member
26
with an outer diameter of Ø
4
. As is known in the industry, the impedance of a coaxial structure is a function of the inner diameter of the outer conductor, the outer diameter of the inner conductor, and the dielectric constant of the material that separates the inner and outer conductors. It is also known that the inclusion of slots in either the inner or outer conductor introduce disturbances in the coaxial structure, resulting in impedance changes in these areas. Referring to
FIG. 3
in the current embodiment, the inner diameter Ø
2
of the shell
50
in section
56
can be approximately 0.1310 inches (3.3274 mm). Also shown in
FIG. 3
are portals
68
. In this embodiment, as noted earlier, the width W
3
of the portals
68
can be approximately 0.065 inches (1.651 mm). Referring to
FIGS. 1
,
5
and
6
, the conductor receiving member, which generally comprises a hollow bore adapted to accommodate the center conductor
46
of the cable
38
, has, in this embodiment, an outer diameter Ø
4
of approximately 0.0625 inches (1.5875 mm). It is a feature of the present invention that the combination of the inner diameter Ø
2
of section
56
, the outer diameter Ø
4
of conductor receiving member
26
, and the width W
3
of portals
68
are adapted such as to optimize the impedance of the connector and enhance the overall RF performance. However, in an alternate embodiment, such as those encountered when using a coaxial cable of either smaller or larger dimensions, the outer diameter Ø
4
of conductor receiving member
46
, the inner diameter Ø
2
of section
56
of back end
60
, and the width W
3
of portals
68
in back end
60
can be any suitable dimension, provided that the combination of dimensions are adapted to achieve the optimized RF performance characteristics of a connector incorporating features of the present invention.
Referring to
FIGS. 1
,
5
and
6
, the conductor receiving member
26
extends into the interior section
56
of connector
6
. The conductor receiving member
26
generally comprises a hollow bore adapted to accommodate the center conductor
46
of the cable
38
. As shown in
FIG. 5
, an outer diameter Ø
4
of the conductor receiving member
26
is generally just large enough to accommodate the center conductor
26
. In one embodiment, the outer diameter Ø
4
of the conductor receiving member
26
is approximately 0.0625 inches (1.5875 millimeters.). However, in an alternate embodiment, the outer diameter Ø
4
of conductor receiving member
26
can be any suitable dimension. It is a feature of the present invention that the outer diameter Ø
4
of the conductor receiving member
26
be adapted, in conjunction with the design of back end
60
(including portals
68
), to optimize the impedance of the connector and enhance the overall RF performance. Referring to
FIG. 6
, the conductor receiving member
26
is adapted to be crimped to the center conductor
46
at crimp points
22
in order to establish a secure mechanical and electrically conductive connection. The crimps are caused to be precisely located at the crimp areas
22
by the alignment of the indentors
102
in each of the portals
68
as shown in FIG.
12
. As will be described in more detail below in conjunction with
FIGS. 9-13
, a stop shoulder
110
in positioner
100
locates connector
6
relative to indentors
102
for the crimping step. By locating the crimp areas
22
in precise locations on the member
26
, the impedance of the connector is optimized and the VSWR of the connector is greatly improved, which are results not realized in other portal crimp designs. It is a feature of the present invention that the design of the portals
68
positions the indenters
102
in the aligned position to locate the crimps over the predetermined crimping areas
22
of connector
6
. The location of the crimp is a factor in the impedance matching and VSWR performance of the connector
6
.
As shown in
FIGS. 1 and 3
, the interior of the connector
6
in the front end
48
is generally cylindrical. Referring to
FIGS. 4 and 6
, a stepped diameter
91
in the front end
48
provides a circumferential shoulder stop
94
within the generally hollow interior
10
against which a generally cylindrical dielectric insert
12
is seated when assembled into the interior
10
. The dielectric insert
12
is generally cylindrical in form and is provided with a central bore
14
having a chamfered entryway
16
at the receptacle end
18
. The electrical contact
20
is generally supported within the bore
14
before insertion into front end
48
. In one embodiment, the contact
20
may also be provided with a reduced neck portion
24
retained in a relatively reduced neck portion
28
of the bore
14
to help secure the contact
20
within the bore
14
.
The front end
48
of connector
6
may also include a pair of shoulder stops
8
on the exterior shell
86
of the front end
48
. The exterior shell
86
generally comprises a section of the conductive shell
50
. Shoulder stops
8
serve to seat connector
6
against a complimentary shoulder stop
110
in a locator
104
of the crimping tool as shown in
FIG. 11
during the crimping step.
A crimping tool
130
and positioner
100
incorporating features of the present invention are shown in FIG.
8
. The crimping tool
130
generally comprises two handles
132
,
134
that are manually manipulated by squeezing the handles
132
,
134
. Tool
130
may also include a set of indenters secured within crimping port
133
adapted to close against the connector
6
at crimp areas
22
to crimp the conductor
46
to the member
26
. In this embodiment, the tool
130
comprises a standard military commercial hand tool M22520/1-01 or part number AF8 sold by Daniels Manufacturing Corporation, also described in Military Specification MIL-C-22520/1 page 1. In an alternate embodiment, tool
130
could comprise any suitable device adapted to crimp conductor
46
to conductor receiving member
26
at crimp areas
22
. As shown in
FIGS. 6 and 13
, the crimp at crimp areas
22
is adapted to provide a secure mechanical and electrically conductive connection between conductor
46
and conductor receiving member
26
. It is a feature of the present invention to form a high performance, low loss electrical connection between the conductor
46
and contact
20
in a connector
6
, while lowering the applied cost of the connector and cable assembly. Referring to
FIGS. 8
,
12
and
13
, the indenters are adapted to close against a connector
6
(with a cable
38
placed therein) inserted into the tool from a first side
135
. The indenters may be arranged so that two pairs of opposed indenters dies provide pairs of indents at four equally spaced crimp areas
22
.
A set of indenters
102
, is shown in
FIGS. 8-13
. Positioner
100
is generally adapted to precisely align and position connector
6
within the tool
130
for the crimping operation. Positioner
100
is mountable to tool
130
on side
136
of tool opposite to crimping port
133
. Locating pin
108
and retaining screws
106
are adapted to be received in complimentary receptacles on side
136
of tool
130
in order to align and secure positioner
100
to tool
130
. Positioner
100
can also include a spring-loaded locator shaft
104
that is adapted to receive connector
6
. Referring to
FIG. 9
, locator shaft
104
is generally cylindrical and comprises first section
111
, a second section
113
and a third section
115
. Locator shaft
104
is generally adapted to be inserted into aperture
116
of positioner
100
. The second section
113
generally has a smaller diameter than the first or third sections
111
,
115
.
Locator shaft
104
can include a reduced-diameter forward section
117
defining a forwardly facing ledge
114
which abuts a correspondingly rearwardly facing ledge
122
defined by a reduced diameter forward portion
119
of aperture
116
within which forward section
117
of shaft
104
is to be disposed. Locator shaft
104
can also include an annular collar
118
at its rearward end that is disposed with an enlarged rearward aperture section
120
of aperture
116
. The rearwardly facing ledge
122
is defined between the rearward aperture section
120
and aperture
116
to retain locator shaft
104
assembled to positioner
100
. Rear end
124
of locator shaft
104
is spring biasedly engaged by compression spring
126
mounted within rearward aperture section
120
and held therein by threaded insert
128
. Alternatively, any suitable means can be used to retain locator shaft
104
in aperture
116
. Locator shaft
104
described above receives plug connector
6
A. A modified shaft not shown is used to receive receptacle connector
6
B. Like shaft
104
, the modified shaft receives receptacle
88
to precisely position portals
68
to accept indenters
102
.
Referring to
FIGS. 8
,
10
and
11
, as positioner
100
initially mounts to tool
130
, leading edge
112
of locator shaft
104
abuts a stop shoulder
150
. As the mounting of positioner
100
to tool
130
continues, the locator shaft
104
is pushed back against the force of spring
126
as shown in FIG.
10
. In other words, spring
126
ensures that locator shaft
104
maintains an abutting relationship with stop shoulder
150
. Due to this arrangement, locator shaft
104
is precisely positioned relative to indentors
102
. With the positioner fully mounted to tool
130
, connector
6
can be precisely crimped to coaxial cable
38
as will be explained in more detail below.
Referring to
FIGS. 10 and 11
, locator shaft
104
can also include a stop shoulder
110
adapted to abut to a complimentary stop shoulder
8
of connector
6
when the connector
6
is inserted into the shaft
104
. When connector
6
abuts stop shoulder
110
, connector
6
is accurately located in the positioner
100
for a crimping operation. Since positioner
100
is accurately located relative to indentors
102
, connector
6
is also accurately positioned relative to indentors
102
.
FIGS. 8 and 10
are illustrative of the general assembly of connector
6
and cable
38
prior to insertion into the tool
130
.
FIG. 11
illustrates the basic positioning of connector
6
inserted into a locator shaft
104
with a cable
38
inserted into the connector
6
. Referring to
FIG. 6
, generally, the cable
38
is inserted into the connector
6
by exposing and flaring the cable braid
42
, then feeding the exposed conductor
46
and dielectric layer
44
through the hollow bore
58
. The conductor
46
is funneled into the conductor receiving member
26
and the braid
42
travels outside bore
58
by the chamfer portions
25
as shown in FIG.
6
. After the cable
38
has been inserted into the connector
6
and the conductor receiving member crimped as described herein, a crimping ferrule
80
is placed over the back end
60
as shown in FIG.
6
and crimped thereto, preferably, with a subsequent crimp process performed with a known crimping tool.
For crimping of the center conductor
46
, a connector
6
and cable
38
are inserted into positioner
100
and tool
130
as shown in FIG.
11
. Referring to
FIG. 12
, the portals
68
each engage an indentor
102
upon actuation of the tool
130
. By squeezing the handles
132
,
134
of tool
130
, the indenters
102
are caused to crimp contact
20
at crimp locations
22
, causing the crimping of conductor
46
as shown in FIG.
13
.
Referring to
FIGS. 11 and 13
, in an example of one embodiment incorporating features of the present invention, when properly positioned against stop shoulder
150
of tool
130
, an outer edge
112
of locator shaft
104
is a distance D
5
of approximately 0.126 inches (3.2004 mm) from the centerlines of indenters
102
, as described in Military Specification MIL-C-22520/1.
A cross-sectional view of a mated pair of complimentary connectors
6
A and
6
B is shown in FIG.
7
. Connector
6
A comprises a plug
36
, while connector
6
B comprises a receptacle
34
. As seen in
FIG. 7
, the connectors
6
A,
6
B could be mated, so that a gap L exists between connector housings R, H. Preferably, gap L is approximately 0.045 inches (1.143 millimeters). When connector
6
A is properly mated with the connector
6
B, a nominal distance D
1
between a far end of retention clips
90
on each of the connectors
6
A and
6
B can be approximately 0.578 inches (14.68 millimeters).
FIGS. 14 and 15
are graphical representations of actual performance test data for connectors
6
A and
6
B incorporating features of the present invention assessing connector loss in terms of VSWR versus frequency, in gigaHertz. The tests were performed with the connectors in the mated condition shown in FIG.
7
. The connector housings were 0.045″ (1.143 mm) from a nominal, or fully mated, position.
FIGS. 16 and 17
are graphical representations of actual performance test data of a prior art connector
6
′, shown in
FIG. 18
, when mated with a complementary prior art connector, where the conductor
46
of a typical cable
38
is soldered to contact
26
′.
Connector
6
′ has an asymmetric back end
60
′. Approximately half of back end
60
′ is removed, creating an opening
68
′ that reveals center contact
26
′. Center contact
26
′ includes a solder port
27
′. Once the center conductor (not shown) of the coaxial cable (not shown) is placed within center contact
26
′, solder (not shown) is introduced into solder port
27
′. The solder fuses the center conductor of the coaxial cable to center contact
26
′. Finally, a ferrule (not shown) is placed over opening
68
′ and crimped to the braid (not shown) of the coaxial cable. As with
FIGS. 14 and 15
, these tests were also performed with the connectors in a mated condition such as that shown in FIG.
7
. In other words, the connector housings were arranged 0.045″ (1.143 mm) from a nominal, or fully mated, position. The test data demonstrates the substantial improvement in terms of electrical performance of the connector
6
of the present invention (
FIGS. 14 & 15
) over a solder type conductor termination (
FIGS. 16 & 17
) used with connector
6
′.
In one embodiment, referring to
FIGS. 6 and 7
, the connector
6
is adapted to be used in high frequency applications, such as for example between approximately 1 and 5 gigahertz (“gHz”). Other applications may include the telecommunications industry where a low loss connection is desired.
The size, shape and location of the portals
68
, the outer diameter of the center contact
26
and the inner diameter of shell
50
are each a factor in the performance of the assembled connector
6
. By placing connector
6
at stop shoulder
110
, of positioner
100
, which itself has been placed against stop shoulder
150
of tool
130
, indenters
102
precisely locate the crimp in the connector
6
. The present invention minimizes signal reflections and compensates for those areas of impedance mismatch that cannot otherwise be eliminated within the connector. Thus, the present invention enhances the overall performance of the connector without sacrificing ease of termination.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.
Claims
- 1. An electrical connector member for a coaxial cable comprising:a first section having two or more portals formed therein, each portal adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of a conductor receiving section of an electrical contact extending into the first section; and a second section including a conductive outer shell electrically coupled to the first section; and a dielectric material enclosed by the outer shell in the second section supporting the electrical contact in a central bore of the dielectric material, the dielectric material not surrounding the conductor receiving section, the conductor receiving section having a diameter adapted to receive a center conductor of the cable, wherein an electrical connection formed by crimping the electrical contact to the conductor using the indentors extending through the portals provides a substantially matched impedance in that section of the connector; a void defining an area in the first section surrounding the conductor receiving section; and a crimp ferrule adapted to be inserted over the first section to electrical and mechanically secure a coaxial shield conductor to the connector member and to cover each portal opening to provide an electrical shield against RF leakage from the void area surrounding the conductor receiving section.
- 2. The connector member of claim 1 wherein the first section and the second section of the member are mated together forming an electrically conductive and mechanically secure connection, and the coaxial cable is crimped in the connector member prior to insertion of the connector member into a respective housing.
- 3. The connector member of claim 1 wherein the first section and the second section are machined as a one-piece connector member.
- 4. The connector member of claim 1 wherein the first section includes four portals, each portal being spaced at a location that is 90° from an adjacent portal.
- 5. The connector member of claim 1 wherein required impedance in a crimp section of the connector member formed by the crimping is approximately 50 ohms.
- 6. The connector member of claim 1 wherein the connector member is adapted to propagate a signal having a frequency in the range of 1 to 5 gigaHertz (gHz).
- 7. The connector member of claim 1 wherein a location of a center point of the crimp area on the conductor receiving section is approximately 0.126 inches (3.200 mm) from the front edge of a locator device adapted to position the connector member in the tool.
- 8. An electrical connector member for a coaxial cable comprising:a first section having two or more portals formed therein, each portal adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of a conductor receiving section of an electrical contact extending into the first section; and a second section including a conductive outer shell electrically coupled to the first section; and a dielectric material enclosed by the outer shell in the second section supporting the electrical contact in a central bore of the dielectric material, the dielectric material not surrounding the conductor receiving section, the conductor receiving section having a diameter adapted to receive a center conductor of the cable, wherein an electrical connection formed by crimping the electrical contact to the conductor using the indentors extending through the portals provides a substantially matched impedance in that section of the connector; a void defining an area in the first section surrounding the conductor receiving section; and a retention clip located on a housing of the second section adapted to retain the assembled and crimped connector member in a connector housing.
- 9. An electrical connector member for a coaxial cable comprising:a first section having two or more portals formed therein, wherein each portal extends from a front portion of the first section through a tapered edge along a rear portion of the first section to form a respective groove in the tapered edge, wherein when the connector member is inserted into the crimping tool, the groove aligns the indentors in each portion, and wherein each portal is adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of a conductor receiving section of an electrical contact extending into the first section; a second section including a conductive outer shell electrically coupled to the first section; and a dielectric material enclosed by the outer shell in the second section supporting the electrical contact in a central bore of the dielectric material, the dielectric material not surrounding the conductor receiving section, the conductor receiving section having a diameter adapted to receive a center conductor of the cable, wherein an electrical connection formed by crimping the electrical contact to the conductor using the indentors extending through the portals provides a substantially matched impedance in that section of the connector; and a void defining an area in the first section surrounding the conductor receiving section.
- 10. An electrical connector member for a coaxial cable comprising:an electrically conductive shell; an electrical contact extending along a portion of a center bore of the shell supported by a first dielectric material, the conductive shell comprising: a first section including four portals therein, each portal adapted to align a corresponding indentor device over a respective portion of a conductor receiving section of the electrical contact; a second section electrically connected to the first section, the second section including the dielectric material inserted therein supporting the electrical contact, the conductor receiving section extending out of the first dielectric material and into the first section wherein a center conductor of the cable is adapted to be received through the first section and crimped to the conductor receiving portion inside of the first section; a crimp ferrule adapted to be inserted over the first section to electrically and mechanically secure a shield conductor of the cable to the connector member and to cover each portal opening to provide a shield against RF leakage; and wherein a void defines an area surrounding a crimped section of the electrical contact and an impedance of the crimped section is substantially matched to an impedance of the cable.
- 11. The connector member of claim 10 wherein a centerline between crimp points applied by each indentor device to the conductor receiving section is approximately 0.126 inches (3.2004 mm) from an outer edge of the locator shaft.
- 12. A connector assembly for a coaxial cable comprising:a plug connector mated to a receptacle connector, wherein each of the plug connector and receptacle connector comprises: a conductive shell comprising a first section and a second section, the first section housing an electrical contact disposed within a center bore of a dielectric material inserted therein; a conductor receiving section of the contact extending from the dielectric material into the second section and adapted to receive a center conductor of a first coaxial cable, the second section including four portals in the shell around the conductor receiving section, each portal adapted to receive an indentor of a crimping tool for crimping the conductor receiving section to the center conductor in at least four aligned locations, the second section further including a bore adapted to receive a cable dielectric and center conductor of the first cable on the inside of the bore and a cable shield on an outside of the bore, wherein a void defines an area around a crimp section of the conductor receiving section; and a retention clip on each first section adapted to retain the respective plug connector and receptacle connector in a respective housing member, wherein when the plug connector is coupled to the receptacle connector a nominal distance between a far end of each retention clip is 0.578 inches (14.68 mm).
- 13. An electrical connector for a coaxial cable, the electrical connector comprising:an electrical contact having a conductor receiving section, the conductor receiving section comprising a crimp area; a first portion having a plurality of portals, the conductor receiving section of the electrical contact extending into an open area of the first portion, wherein each portal is adapted to guide an indentor of a crimping tool into a predetermined position over the crimp area of the conductor receiving section of the electrical contact; a second portion electrically coupled to the first portion, the second portion including a conductive outer shell; a dielectric member located inside the second portion and supporting the electrical contact therein, wherein an electrical connection formed by crimping the electrical contact to a center conductor of the coaxial cable using the indentors extending through the portals provides a substantially matched impedance; and a crimp ferrule adapted to be located over the first portion to secure a shield conductor of the coaxial conductor to the first portion and to cover the portals, wherein the crimp ferrule is adapted to provide an electrical shield against RF leakage from the open area at the conductor receiving section.
- 14. A coaxial cable electrical connector comprising:an electrical contact; a first portion having a plurality of portals formed therein, wherein the electrical contact extends into an open area of the first portion, and wherein the portals are each adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of a conductor receiving section of the electrical contact; a second portion electrically coupled to the first section, the second portion comprising a conductive outer shell; a dielectric member located in the outer shell in the second section, the dielectric member supporting the electrical contact therein, wherein an electrical connection formed by crimping the electrical contact to a center conductor of a coaxial cable using the indentors extending through the portals provides a substantially matched impedance; and a retention clip located on the second portion, the retention clip being adapted to retain the coaxial cable electrical connector to a connector housing.
- 15. A coaxial cable electrical connector comprising:an electrical contact; a first section having a plurality of portals formed therein, wherein the electrical contact extends into an open area of the first section, wherein each portal extends through a portion of a tapered edge of the first section to form a respective groove in the tapered edge, wherein each portal is adapted to guide an indentor of a crimping tool into a predetermined position over a crimp area of a conductor receiving section of the electrical contact, and wherein, when the first section is inserted into the crimping tool, the grooves are adapted to align the indentors with the first section; and a second section electrically coupled to the first section, the second section comprising a conductive outer shell.
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A |
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