1. A coaxial cable element comprising: • a body; • at least one central contact mounted in the body with interposed insulation; • a flexible sleeve receiving a coaxial cable and defining a grip portion for gripping by a user; and • a hollow plug including a helical groove for coupling with a complementary connector element; wherein the plug and the sleeve form a single integral unit.

2. A connector element according to claim 1, wherein the plug and the sleeve are distinct parts and include co-operating portions in relief to enable the plug and the sleeve to be fastened together permanently.

3. A connector element according to claim 2, wherein: • the plug includes a rear portion having at least one key on its outside surface; • the sleeve includes a front portion having at least one setback formed in its inside surface; and the key is arranged to be inserted in the setback when fastening the plug and the sleeve together.

4. A connector element according to claim 3, wherein: • the rear portion of the plug includes at least one ring on its outside surface, the ring extending over at least a fraction of the periphery of the rear portion; • the front portion of the sleeve includes a groove formed in at least a portion of the periphery of its inside surface; and • the ring is arranged to be inserted into the groove when fastening the plug on the sleeve.

5. A connector element according to claim 1, wherein the plug is made of plastics material.

6. A connector element according to claim 5, wherein said plastics material is transparent.

7. A connector element according to claim 1, wherein the sleeve is made of plastics material.

8. A connector element according to claim 7, wherein said plastics material includes a coloring additive.

9. A connector element according to claim 1, wherein the plug and the sleeve are made as a single piece.

10. A connector element according to claim 9, wherein the plug and the sleeve are made of plastics material.

11. A connector element according to claim 5 or according to claim 10, wherein the plastics material of the plug and/or the plastics material of the sleeve include(s) phosphorescent additives.

12. A connector element according to claim 1, wherein the plug includes at least one cavity and wherein the connector element includes at least one ring having at least one lug, said lug being configured to co-operate with said cavity so as to hold the body and the plug together.

13. A connector element according to claim 12, wherein the body includes a groove in its outside surface extending around all or part of said outside surface and bordered on one side by a first shoulder, and wherein the connector element includes a resilient ring capable of moving out from the groove beyond the first shoulder, and a flat split ring that is freely movable in translation in the groove and that is capable of coming into abutment against the first shoulder.

14. A connector element according to claim 12, wherein the front face of the plug is cut into a cup shape.

15. A connector element according to claim 12, wherein the plug and/or the sleeve include a projection projecting from their outside surface, and wherein the plug and/or the sleeve present a profile that is elliptical or oval. Dated this 6th day of October 2009. The present invention relates to a coaxial cable element comprising: • a body; • at least one central contact mounted in the body with interposed insulation; • a flexible sleeve receiving a coaxial cable and defining a grip portion for gripping by a user; and • a hollow plug including a helical groove for coupling with a complementary connector element; wherein the plug and the sleeve form a single integral unit.

The present invention relates to a coaxial connector element. More particularly, the
invention applies to coaxial connector elements for high resolution digital television of the
BNC (bayonet Neill-Concelman) type, such connector elements being used for example to
connect coaxial cables interconnecting various radiofrequency modules mounted in a bay.
Nevertheless, the invention is not limited to this particular type of connector.
Background of the invention
The grip surface of known connector elements for this type of application is
defined only by the plug. As a result the grip surface is of relatively small extent, thereby
making a coaxial cord including such a connector element difficult to manipulate in a
dense environment or blind, where such an environment may be constituted for example
by a bay for high resolution digital television.
It is known, e.g. from US 312 814 to improve grip of a connector element by
increasing the length of the plug, thereby requiring longer internal parts for the connector
element, such as the body of the connector element or the central contact, and/or requiring
special tooling to be developed in order to crimp the cable.
Application US 2002/0039853 discloses a connector element comprising a sleeve
and a plug, the sleeve being constrained to turn with the plug by using an additional,
intermediate part so as to enable the sleeve to be used as a grip portion. That solution
presents the drawback of requiring recourse to an additional part for connecting the sleeve
to the plug and of requiring a dual-injection method to be used for making the sleeve so as
to obtain a sleeve that is mechanically sufficiently rigid to enable it to be gripped by a
user, and sufficiently flexible to enable a cable to be passed through an opening provided
in the sleeve.
Patent US 4 746 305 discloses a coaxial connector having a plug in two portions
without a flexible sleeve making it possible to accompany the movements of a coaxial
cable to which the connector is connected.
Patent US 6 808 407 also discloses a coaxial connector comprising a two-part plug
without a flexible sleeve.
Object and summary of the invention
There exists a need to make it easier for a user to grip a coaxial cord including a
coaxial connector element in an environment that is dense, or blind, and for this to be
achieved in a manner that is simple and inexpensive.
The invention seeks to satisfy this need and it achieves this object by a coaxial
cable element comprising:
• a body;
• at least one central contact mounted in the body with interposed insulation;
• a flexible sleeve receiving a coaxial cable and defining a grip portion for gripping
by a user; and
• a hollow plug including a helical groove for coupling with a complementary
connector element;
wherein the plug and the sleeve form a single integral unit.
By making the plug and the sleeve as an integral unit, the invention enables the
sleeve to be used as a grip portion.
Unlike known solutions, the invention enables a grip portion to be obtained of
greater or shorter length depending on the intended application, without it being necessary
to modify the length of the body and of the internal parts of the connector element, in
particular of the central contact and of the insulation of the connector.
The sleeve is advantageously configured to protect the coaxial cable and to
accompany the movements thereof.
By way of example, the sleeve is in direct contact with the coaxial cable. The
sleeve may be configured to allow the coaxial cable to move, e.g. in twisting, when
received in the sleeve.
In a first exemplary embodiment of the invention, the plug and the sleeve are
distinct parts and include co-operating portions in relief to enable the plug and the sleeve
to be fastened together permanently.
In this first exemplary embodiment, the plug and the sleeve are fastened together in
permanent manner, which means that the two parts assembled together in this way cannot
be taken apart by a user.
The plug includes a rear portion advantageously having at least one key on its
outside surface, the sleeve including a front portion advantageously having at least one
setback formed in its inside surface, and the key is advantageously arranged to be inserted
in the setback when fastening the plug and the sleeve together, thereby preventing the
sleeve and the plug from turning relative to each other.
The rear portion of the plug advantageously includes at least one ring on its outside
surface, the ring extending over at least a fraction of the periphery of said rear portion, the
front portion of the sleeve advantageously includes a groove arranged in at least a fraction
of the periphery of its inside surface, and the ring is advantageously arranged to be
inserted in the groove when the plug and the sleeve are fastened together, thereby
preventing the sleeve and the plug from translating relative to each other.
By means of the invention, the plug and the sleeve are secured to each other
without requiring an additional part.
The plug is advantageously made of a plastics material, e.g. by injection molding,
thereby enabling electrical insulation properties to be provided that enable a user to use the
connector element in complete safety when connecting a coaxial cable to the bay. In
addition, the use of a plastics material leads to a saving in weight that may also constitute
an economic advantage.
Said plastics material is advantageously transparent, thereby enabling the body of
the connector element to be made visible to the user.
The sleeve is advantageously made of plastics material, said plastics material
including coloring, for example, thereby enabling a coding type function to be added to
the sleeve and making the sleeve easier to identify by a user.
In a second exemplary embodiment of the invention, the plug and the sleeve are
made as a single piece, e.g. by dual injection or by overmolding.
The plug and the sleeve may be made of plastics material, for example.
In the second exemplary embodiment, the invention enables the number of parts to
be reduced even further, the single piece acting both as a plug and as a sleeve, thereby
simplifying assembly of the connector element and providing the user with electrical
protection when handling the connector element.
The plastics material of the plug and/or that of the sleeve advantageously include
phosphorescent additives, thereby enabling the connector element to be easier to see in
surroundings that are dense and/or dark.
The plug advantageously includes at least one resilient tab projecting towards the
inside, the body advantageously including in its outside surface at least one groove, and
the resilient tab is advantageously arranged to be inserted in the groove when the plug is
mounted on the body.
In a variant, the plug includes at least one cavity and the connector element
includes at least one ring with at least one lug. Said lug is shaped so as to co-operate with
said cavity in such a manner as to prevent movement in translation in either direction
between the body and the plug and to prevent any rotation between these two parts.
The body may include a groove in its outside surface extending over all or a
fraction of said surface and bordered on one side by a first shoulder.
Advantageously, the connector element includes a resilient ring capable of moving
out from the groove beyond the first shoulder and a flat split ring that is freely movable in
translation in the groove and that is capable of coming into abutment against the first
shoulder.
The stopping of the flat ring by the first shoulder of the element enables non-
functional compression of the resilient ring to be avoided by preventing the flat split ring
from moving out from the groove, thereby reducing any risks of the resilient ring being
destroyed.
When connecting such a connector element to a complementary connector
element, the spring function of said connector element is advantageously provided by the
resilient ring bearing against the flat ring, itself bearing against the plug.
By means of the shoulder, the groove may be adjusted to the stroke that
corresponds to the helical groove in the sleeve, thereby enabling the lifetime of the
connector to be increased.
The front face of the plug may be cut into a cup shape, in order to make bayonet
coupling easier.
The plug and/or the sleeve may include at least one projection projecting from their
outside surface and may present a profile that is oval or elliptical, thereby facilitating
positioning relative to the helical groove of the plug, facilitating grip by a user, and
possibly acting as a visible connection indicator.
In the invention, the assembly constituted by the plug and the sleeve may for
example be separable from the body, thus making it possible, where appropriate, to
perform maintenance operations on the connector element without destroying the plug
and/or the sleeve. In addition, the invention makes it possible to improve guidance
between the body and the assembly constituted by the plug and the sleeve.
By way of example, the connector element may be of the BNC type.
In non-limiting manner, the connector element may for example be a connector
element presenting an impedance of 75 ohms (?).
Other exemplary embodiments of the invention also provide a coaxial cord
comprising:
• a coaxial cable; and
• a connector element as defined above mounted on at least one end of the cable.
Brief description of the drawings
Other advantages and characteristics of the invention appear on reading the
following description of non-limiting embodiments given with reference to the
accompanying drawings, in which:
• Figure 1 is an exploded view of a connector element of the invention;
• Figure 2 shows a plug and a sleeve in a first embodiment of the invention prior to
being fastened together;
• Figure 3 is a section view of the plug, the sleeve, and the body in the first
embodiment of the invention;
• Figure 4 is a perspective view of a portion of a coaxial cord in accordance with
the first embodiment of the invention;
• Figure 5 is a section view of the plug and the sleeve in a second embodiment of
the invention; and
• Figures 6 to 8 are respectively an overall view of the body, the plug, and the
sleeve in a third embodiment of the invention, a section view when the plug is mounted on
the body and a detail view of the Figure 6 connector element.
More detailed description
Figure 1 shows an example of a connector element given overall reference 1 and
constituting a first embodiment of the invention.
The connector element 1 presents a longitudinal axis X and includes a sleeve given
overall reference 2 and a hollow plug given overall reference 3 that are shown in Figure 1
prior to being fastened together, the sleeve 2 and the plug 3 in this first embodiment being
two distinct parts.
The connector element 1 also includes a body given overall reference 4, a central
contact 5, insulation that is not shown, a gasket 6, a resilient ring 7, and a ferrule 8 for
crimping onto a coaxial cable.
As can be seen in Figure 3, the body 4 includes a rear portion 9 having a groove 10
formed in the outside surface thereof for a purpose that is described below. In the example
described, the groove 10 is an annular groove.
Figure 2 shows an example of a sleeve 2 and a plug 3 of the invention prior to
them being fastened together.
As can be seen, the hollow plug 3 has a front portion 11 in which a helical groove
12 is provided that enables the plug to be fastened to a complementary connector by
bayonet coupling. The plug 3 also has a rear portion 13 with portions in relief 14 and 15
arranged on its outside surface. In the example described, two keys 14 are made integrally
with the outside surface of the rear portion 13 of the plug 2 and are diametrically opposite
each other, however these two keys could be arranged differently on said outside surface.
The rear portion 13 of the plug 3 also includes a ring 15 that, in the example
described, extends around the outside surface of said rear portion 13 of the plug 3.
As shown in Figure 3, the rear portion 13 also includes two resilient tabs 16
projecting outwards for a purpose that is described below.
By way of example, the plug 3 is made by injection molding a transparent plastics
material, e.g. a polycarbonate.
The sleeve 2 defines a housing 17 suitable for receiving the rear portion 13 of the
plug 3 and a coaxial cable 18, as shown in Figure 4. As can be seen in Figure 2, the sleeve
has a front portion 19 with an inside surface that is provided with portions in relief 20 and
21.
In the example described, the inside surface of the front portion 19 of the sleeve 2
includes two setbacks 20 extending longitudinally, and an annular groove 21 extending
around the periphery of the inside surface of the front portion 19 of the sleeve.
By way of example, the sleeve 2 is made of a flexible plastics material, e.g.
polyurethane, and this plastics material may include a coloring additive, so as to give a
coding function to the sleeve in addition to functions of protecting the coaxial cable and
accompanying the movements thereof.
The sleeve 2 and the plug 3 may both be made of plastics material including
phosphorescent additives, advantageously selected appropriately for the corresponding
plastics material.
As can be seen in Figure 4, the plug 3 may present an outside surface that does not
have any portions in relief, so as to define a surface that is smooth.
The sleeve 2 may advantageously be arranged in such a manner that its outside
surface defines a grip portion 22, this grip portion 22 being obtained for example by
knurling or by forming a rough zone.
In the first embodiment of the invention, when assembling the connector element
1, the sleeve 2 and the plug 3 are initially fastened to each other, in such a manner as to
ensure that they cannot subsequently be taken apart by a user. As shown in Figure 2, the
rear portion 13 of the plug 3 is inserted into the front portion 19 of the sleeve 2. Each key
14 is then received in a corresponding setback 20. Furthermore, the ring 15 is received in
the annular groove 21.
The assembly obtained in this way is then mounted on the body 4 and each
resilient tab 16 comes to bear in the annular groove 10 to hold said assembly on the body
4.
The invention is not restricted to any particular number or shape for the keys 14,
the ring 15, the setback 20, the groove 21, the resilient tab 16, and the groove 10.
Figure 5 shows the second embodiment of the invention. As can be seen, the plug
3 may be made integrally with the sleeve 2, e.g. by dual injection or by overmolding a
plastics material. The inside surface of the sleeve 2 has resilient tabs 16 similar to those
described with reference to Figure 3.
The invention is not limited to the examples described above.
Although the examples described relate to a connector element for connecting to a
corresponding connector element by means of a bayonet coupling to produce a BNC type
connector, the invention may be applied to connector elements using other types of
coupling.
Although, in the examples described, the connector element has only one central
contact, the invention does not exclude the presence of more than one central contact for
the connector element, e.g. two central contacts.
Figure 6 shows a third embodiment of the invention.
In this embodiment, the plug 3 and the sleeve 2 may be made as a single piece, as
described for the second embodiment of the invention, or they may be made as two
distinct parts that are fastened together, as described for the first embodiment of the
invention.
As shown, in the example under description, the plug 3 and the sleeve 2 include a
projection 40 extending along the longitudinal axis X. This projection 40 may extend over
the entire length of the sleeve and/or of the plug or over a portion only thereof. The
projection 40 in the example described extends continuously, but in a variant it could
extend discontinuously.
As shown in Figure 6, at least towards the front end 41 of the plug 3, the projection
40 may be hollow, so as to define a cavity 42 for a purpose that is described below. In the
embodiment described, the plug 3 and the sleeve 2 include two diametrically-opposite
projections 40 each defining a cavity 42.
Still in the embodiment shown, the plug 3 and the sleeve 2 present a profile that is
oval or elliptical.
There follows a description of the body 4 with reference to Figure 8.
As may be seen, the body includes a middle portion 45 within which there is
defined a main groove 43 that, in the embodiment described, extends all away around the
longitudinal axis (X) of the body. A secondary groove 44 is formed in said main groove
43, at the rear end thereof.
As shown in Figure 8, the main groove 43 is bordered towards the front by a collar
51 and towards the rear by a second shoulder 47. The secondary groove 44 is bordered
towards the front of the body 4 by a first shoulder 46 formed in the bottom of the main
groove 43, and towards the rear of the body 4 by a second shoulder 47. A resilient ring 48
is received in the middle portion 45, the ring 48 coming into rear abutment against a flat
split ring 50 that is mounted by force in the secondary groove 44 and that prevents forward
movement in translation against the first shoulder 46. The resilient ring 48 can move
forwards in the middle portion 45 beyond the secondary groove 44, e.g. coming into
abutment against the collar 51.
The flat ring 50 constitutes a rear stop against movement in translation of the
resilient ring 48, serving, once assembly has been completed, to prevent the resilient ring
48 from escaping from the main groove 43.
As shown in Figures 6 and 8, the connector element 1 in the embodiment shown
may also include a ring 52 with two lugs 53. In the embodiment described, each lug 53 is
configured to be received inside a cavity 42, such that the ring 52 is prevented from
turning relative to the plug 3. When the assembly formed by the sleeve 3 and the plug 2 is
mounted on the body 4, said assembly is taken towards the body 4 by being slid along the
coaxial cable until the ring 52 snap-fastens in the groove 42 between the second shoulder
47 and the flat split ring 50, as shown in Figure 7.
The invention provides a solution that is less expensive than known solutions for
improving grip on a coaxial cord, and it does so by simplifying factory assembly of the
connector element, by making use of fewer component parts for making the connector
element, and by presenting a solution that is lighter in weight.
The invention also makes it possible to use the same plug and/or the same plug for
coaxial cables of different diameters.
WE CLAIM :
1. A coaxial cable element comprising:
• a body;
• at least one central contact mounted in the body with interposed insulation;
• a flexible sleeve receiving a coaxial cable and defining a grip portion for gripping
by a user; and
• a hollow plug including a helical groove for coupling with a complementary
connector element;
wherein the plug and the sleeve form a single integral unit.
2. A connector element according to claim 1, wherein the plug and the sleeve are
distinct parts and include co-operating portions in relief to enable the plug and the
sleeve to be fastened together permanently.
3. A connector element according to claim 2, wherein:
• the plug includes a rear portion having at least one key on its outside surface;
• the sleeve includes a front portion having at least one setback formed in its inside
surface; and
the key is arranged to be inserted in the setback when fastening the plug and the
sleeve together.
4. A connector element according to claim 3, wherein:
• the rear portion of the plug includes at least one ring on its outside surface, the
ring extending over at least a fraction of the periphery of the rear portion;
• the front portion of the sleeve includes a groove formed in at least a portion of the
periphery of its inside surface; and
• the ring is arranged to be inserted into the groove when fastening the plug on the
sleeve.
5. A connector element according to claim 1, wherein the plug is made of plastics
material.
6. A connector element according to claim 5, wherein said plastics material is
transparent.
7. A connector element according to claim 1, wherein the sleeve is made of plastics
material.
8. A connector element according to claim 7, wherein said plastics material includes a
coloring additive.
9. A connector element according to claim 1, wherein the plug and the sleeve are made
as a single piece.
10. A connector element according to claim 9, wherein the plug and the sleeve are made
of plastics material.
11. A connector element according to claim 5 or according to claim 10, wherein the
plastics material of the plug and/or the plastics material of the sleeve include(s)
phosphorescent additives.
12. A connector element according to claim 1, wherein the plug includes at least one
cavity and wherein the connector element includes at least one ring having at least
one lug, said lug being configured to co-operate with said cavity so as to hold the
body and the plug together.
13. A connector element according to claim 12, wherein the body includes a groove in its
outside surface extending around all or part of said outside surface and bordered on
one side by a first shoulder, and wherein the connector element includes a resilient
ring capable of moving out from the groove beyond the first shoulder, and a flat split
ring that is freely movable in translation in the groove and that is capable of coming
into abutment against the first shoulder.
14. A connector element according to claim 12, wherein the front face of the plug is cut
into a cup shape.
15. A connector element according to claim 12, wherein the plug and/or the sleeve
include a projection projecting from their outside surface, and wherein the plug and/or
the sleeve present a profile that is elliptical or oval.
Dated this 6th day of October 2009.

The present invention relates to a coaxial cable element comprising:
• a body;
• at least one central contact mounted in the body with interposed insulation;
• a flexible sleeve receiving a coaxial cable and defining a grip portion for gripping
by a user; and
• a hollow plug including a helical groove for coupling with a complementary
connector element;
wherein the plug and the sleeve form a single integral unit.