Electrical connectors – Including or for use with coaxial cable – Having screw-threaded or screw-thread operated cable grip
Reexamination Certificate
2000-03-22
2001-09-25
Nguyen, Khiem (Department: 2839)
Electrical connectors
Including or for use with coaxial cable
Having screw-threaded or screw-thread operated cable grip
Reexamination Certificate
active
06293824
ABSTRACT:
The present invention relates to an electrical connector element for mounting on an electric cable, and to a method of mounting it.
More particularly, the invention relates to connector elements which are for mounting on cables having a helically-corrugated outer conductor.
In the present description, the term “helically-corrugated conductor” is used to mean a tubular conductor having corrugations whose peaks follow helixes around the axis of the cable, said corrugations forming a thread around the outer conductor of the cable.
BACKGROUND OF THE INVENTION
Coaxial connector elements are already known that are designed to be mounted at the ends of such cables. Thus, for example, the connector element described in U.S. Pat. No. 5,154,636 comprises a body supporting a central contact which is held by insulation on the axis of the connector element, a ring which is organized to be capable of being screwed onto the helically-corrugated outer conductor of the cable, and a washer that is interposed between the body and the ring. The body and the ring can screw together to enclose the washer to constitute the connector element.
The ring has a frustoconical mouth directed towards the body and the washer has a frustoconical surface that is complementary to said mouth.
After the ring has been screwed onto the cable, the outer conductor passes through the ring and its end is in register with the frustoconical mouth of the ring. By using a suitable tool, this end is flared so as to be pressed against said mouth.
The washer is then pressed against the ring, with its frustoconical surface clamping the flared end of the outer conductor against the frustoconical mouth of the ring, after which the body is screwed to the ring, thereby compressing the washer against the ring and permanently locking the connector element to the outer conductor of the cable, and thus to the cable itself, while also connecting the inner conductor of the cable to a pin that is secured to the central contact of the body.
The function of the washer is to prevent the body from causing the cable to rotate while the outer conductor is being clamped, since that could cause the cable to become unscrewed in the ring.
Such a connector element gives satisfaction as to its electrical characteristics.
However, it gives rise to a large number of handling operations which make it lengthy and fiddly to put into place at the end of a cable.
The connector element is initially supplied in the assembled condition, thereby guaranteeing that all of its component parts are present, and protecting these parts during transport, however the connector element then needs to be disassembled in order to be mounted on a cable, and such mounting is performed on site.
To sum up, for mounting purposes, it is necessary to take apart the connector element, to screw the ring onto the outer conductor, to flare the end thereof, to put the washer into place, and to screw the body to the ring.
OBJECTS AND SUMMARY OF THE INVENTION
The present invention seeks to simplify such a connector by minimizing the number of component parts and also the number of operations that need to be performed to mount it on the end of the helically-corrugated outer conductor of a coaxial cable.
The present invention provides a connector element for mounting on an electric cable having at least an inner conductor and a helically-corrugated outer conductor, said connector element comprising:
a body supporting at least one internal contact held by insulation in the vicinity of the axis of the connector element; and
a ring having a tapped first segment for securing the ring to the body by screw engagement, and a second tapped segment whereby said ring can be screwed on the helically-corrugated outer conductor of the cable, causing an end segment thereof to project towards the body, thereby holding the cable in alignment with the connector element so that the outer conductor of the cable is electrically connected to the body and the inner conductor(s) of the cable is/are electrically connected to the internal contacts of the body,
the body and the ring being organized in such a manner that screwing one to the other causes the end segment of the outer conductor to be clamped against the mouth of the tapped second segment of the ring,
wherein the tapped segments of the ring have screw threads that are oppositely-handed relative to each other, such that screwing the body into the ring while the ring is prevented from rotation causes the body and the cable to be move towards each other.
It will be understood that in accordance with the invention the screw tightening direction between the body and the ring is opposite from the screw tightening direction between the ring and the cable.
The connector element of the invention thus provides a simple and low cost solution to the requirements stated above.
Because the screw tightening directions are reversed firstly between the ring and the body and secondly between the cable and the ring, if the body causes the cable to rotate while it is being screwed to the ring, that can only serve to tighten the ring to the cable and thus increase the clamping on the end of the cable between the body and the ring.
Consequently, the invention makes unnecessary the washer which used to be interposed between the prior art connector elements.
In addition, the operator installing the connector element of the invention at the end of a coaxial cable does not need to pay attention to any risk of one part loosening relative to another while the connector element is being assembled.
In a particular embodiment of the invention, the ring and the body leave sufficient space between them when they begin to be screwed together for receiving a plurality of turns of the helically-corrugated outer conductor of the cable.
Thus, when the ring is screwed to the cable, a plurality of turns of the outer conductor project from the mouth of the ring, and these turns are held captive between the ring and the body and are pressed one against another when the ring is screwed to the body, thereby providing retention means for the cable and making it unnecessary to use a special tool for flaring the end of the conductor in the mouth of the ring.
Advantageously, a frustoconical projection is provided which is preferably carried by the body at its rear end, in register with the mouth of the second tapped segment of the ring, said projection being pushed back against said mouth when the body is screwed into the ring.
The present invention is particularly, but not exclusively, well suited to being applied to connector elements that are coaxial in structure.
The present invention also provides a method of mounting an electrical connector element as described above on a cable comprising at least an inner conductor and a helically-corrugated outer conductor, said connector element including a frustoconical projection, preferably carried by the body at its rear end, in register with the mouth of the second tapped segment of the ring, said method consisting in:
screwing the body into the ring while leaving sufficient space between the frustoconical projection and the mouth of the second tapped segment to receive an end segment of the outer conductor of the cable;
screwing the assembly made up in this way onto the outer conductor of the cable until an end segment of the cable projects beyond said ring between the ring and the body; and
screwing the body into the ring while preventing the ring from rotating, thereby causing the body and the cable to move towards each other.
It will be understood that this method is easily implemented since, because of the invention, there is no risk of the cable unscrewing from the ring while the body is being screwed to the ring, even if, by friction, the body causes the cable to rotate.
REFERENCES:
patent: 0495467 (1992-01-01), None
patent: 0551092 (1993-01-01), None
patent: 0629025 (1994-06-01), None
patent: 2303749 (1997-02-01), None
Baffert Jean-Marc
Coste Catherine
Guerin Maurice
Nasri Javaid
Nguyen Khiem
Radiall
Schweitzer Cornman Gross & Bondell LLP
LandOfFree
Connector element for mounting on a electric cable having a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Connector element for mounting on a electric cable having a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Connector element for mounting on a electric cable having a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2458622