1. A 7-16 flanged receptacle comprising a tubular body including an outside thread and a fastener flange perpendicular to the longitudinal axis of the body, and a central contact mounted in said body with an insulator being interposed, the receptacle including a tubular metal part forming an outer contact mounted as a tight fit in the inside wall of said body with limited ability to move longitudinally relative thereto.

2. A receptacle according to claim 1, wherein said body is a single part of molded plastics material.

3. A receptacle according to claim 2, wherein said body is obtained by injection molding.

4. A receptacle according to claim 2, wherein the tubular body is made of a plastics material selected from the group comprising: polyaryl-amides, polyamide-imides, and polyphenylene sulfides.

5. A receptacle according to claim 1, wherein the part forming the outer contact includes on its outside a peripheral bead bearing with interference against a bearing surface set back in the inside wall of the body. The present invention relates to a 7-16 flanged receptacle comprising a tubular body including an outside thread and a fastener flange perpendicular to the longitudinal axis of the body, and a central contact mounted in said body with an insulator being interposed, the receptacle including a tubular metal part forming an outer contact mounted as a tight fit in the inside wall of said body with limited ability to move longitudinally relative thereto.

The present invention relates to a 7-16 coaxial flanged receptacle.
Such receptacles are referred to as 7-16 receptacles because they present an inside
contact diameter of 7 millimeters (mm) and an outside contact diameter of 16 mm, and
they are in widespread use in telecommunications equipment for connecting
radiofrequency lines for which there are very severe performance requirements in terms of
losses and passive intermodulation.
In general, such flanged receptacles are situated as inputs/outputs of duplexer
filters, on antennas, and more generally on other pieces of equipment situated between
those elements, such as mast amplifiers, lightning arrestors, etc.
To obtain as great as possible a reduction in the intermodulation phenomenon, it is
conventional to use receptacles comprising a machined solid body presenting an outside
thread and a fastener flange extending perpendicularly to the longitudinal axis of the body,
the flange being substantially square in shape with four holes for passing mounting
screws.
Those receptacles have the advantage of minimizing junction zones, which are
sources of intermodulation, but the drawback of being expensive, heavy, and difficult to
mount. Mounting conventional receptacles by means of four screws engaged in the
corresponding holes of the flange is difficult when it is desired to minimize
intermodulation, since it is necessary to obtain a good distribution of pressures in the
contact zones.
Proposals have also been made to replace the brass that is conventionally used with
an alloy of lighter weight based on zinc (Zamak) or aluminum.
The above-described problems remain substantially the same, but the parts are less
expensive to produce since the tubular bodies can be obtained by molding under pressure.
The drawback is such that receptacles are difficult to protect and they are very sensitive to
corrosion which requires the conductor to be subjected to surface treatment.
Proposals have also been to provide 7-16 coaxial receptacles comprising a two-
material tubular body, the flange being made of a plastics material that is overmolded or
force-fitted on the tubular body that is made of brass.

That solution does not solve the problems associated with final assembly using
screws engaged in the holes of the flange.
Furthermore, it is found that large amounts of deformation in use under stress
continue because of a relaxation phenomenon that causes contact pressures to decrease
over time.
The present invention seeks to provide a 7-16 coaxial flanged receptacle that is
very easy to mount, enabling excellent intermodulation performance to be obtained, light
in weight, that presents good corrosion resistance, and a fabrication cost that is low.
The present invention provides a 7-16 flanged receptacle comprising a tubular
body including an outside thread and a fastener flange perpendicular to the longitudinal
axis of the body, and a central contact mounted in said body with an insulator being
interposed, the receptacle including a tubular metal part forming an outer contact mounted
as a tight fit in the inside wall of said body with limited ability to move longitudinally
relative thereto.
The term "limited ability to move longitudinally" is used in the invention to mean a
movement of 0.05 mm to 1 mm depending on the axial force applied during the mounting
of the receptacle on a piece of equipment or when tightening a plug on the receptacle.
In the invention, the central contact and the metal tubular part forming the outer
contact are preferably both made of brass.
Preferably, said body is a single part of molded plastics material.
The tubular body is advantageously made of an injected-molded plastics material,
selected from the group comprising: polyaryl-amides (PAAs), polyamide-imides (PAIs),
and polyphenylene sulfides (PPSs), preferably filled with fibers made of glass, or of
carbon, or of an optionally conductive metal material.
In a variant, the tubular body may be made of metal, e.g. an alloy of zinc or
aluminum, that has been subjected to anti-corrosion surface treatment, in particular
chrome passivation.

In the invention, the tubular metal part forming the outer contact is held in the
body, prior to the receptacle being put into place on a piece of equipment, preferably by a
small amount of clamping or by clip-fastening or by deformation of the facing inside wall
of the tubular body.
Other advantages and characteristics of the invention appear on reading the
following description of a non-limiting embodiment given with reference to the
accompanying drawings, in which:
• Figure 1 is a section view of the flanged receptacle of the invention;
• Figure 2 is an exploded perspective view of the components of the receptacle
shown in Figure 1; and
• Figure 3 is an exploded section view in half-section showing the components of
the receptacle of the invention, and Figures 3 and 4 show the receptacle seen from two
different angles.
The flanged receptacle shown in the drawings comprises a tubular body given
overall reference 1, a tubular metal part made of brass given overall reference 2 received
inside said tubular body and forming an outer, ground contact, a central brass contact 3
having a male contact end 3a and a female contact end 3b, and insulation 4 interposed
between the central contact 3 and the outer, ground contact 2.
The tubular body 1 presents an outside thread 5 and a flange 6 in the form of a
square with rounded corners provided in its four corners with holes 7 for passing mounting
screws (not shown).
In its inside wall, the body presents a set-back bearing surface 8 that receives
bearing thereagainst an annular bead 9 of the part 2 forming the outer, ground contact.
The tubular body 1 of the receptacle of the invention is made by injection molding
PAA.
In a variant, it is possible to use PAI or PPS as the plastics material.

The plastics material used presents a high degree of rigidity, a low degree of creep,
and a coefficient of thermal expansion that is close to that of brass.
The interference between the bead 9 on the part forming the outer contact 2 and the
facing bearing surface 8 of the body enables the components of the receptacle to stay held
together prior to being mounted on equipment. A small amount of sliding of the part
forming the outer contact might occur during mounting of the receptacle under the action
of the applied tightening force, or when tightening a plug on the receptacle, and the
intermodulation characteristics are unmodified in the event of incorrect mounting.

WE CLAIM:
1. A 7-16 flanged receptacle comprising a tubular body including an outside thread and a
fastener flange perpendicular to the longitudinal axis of the body, and a central contact
mounted in said body with an insulator being interposed, the receptacle including a tubular
metal part forming an outer contact mounted as a tight fit in the inside wall of said body
with limited ability to move longitudinally relative thereto.
2. A receptacle according to claim 1, wherein said body is a single part of molded plastics
material.
3. A receptacle according to claim 2, wherein said body is obtained by injection molding.
4. A receptacle according to claim 2, wherein the tubular body is made of a plastics
material selected from the group comprising: polyaryl-amides, polyamide-imides, and
polyphenylene sulfides.
5. A receptacle according to claim 1, wherein the part forming the outer contact includes
on its outside a peripheral bead bearing with interference against a bearing surface set
back in the inside wall of the body.

The present invention relates to a 7-16 flanged receptacle comprising a tubular body including an outside thread and a fastener flange perpendicular to the longitudinal axis of the body, and a central contact mounted in said body with an insulator being interposed, the receptacle including a tubular metal part forming an outer contact mounted as a tight fit in the inside wall of said body with limited ability to move longitudinally relative thereto.