Automatic Splice with Integral Center Stop
发布时间:2014-03-11ABSTRACT
Connectors for longitudinally splicing two lengths of cable or other electrical connectors together, commonly referred to as “automatic splices,” have long been known. Such devices are typically used by power utility linemen to quickly splice lengths of overhead or otherwise suspended high voltage cable together and have become a mainstay in the electrical utility industry. Originally developed for emergency restoration, the automatic splice has evolved into a nominal construction component for overhead power lines, and has been extensively used in the industry for over seventy years.
An early version of the automatic splice is disclosed in U.S. Pat. No. 3,205,300 to Becker. The opposed ends of Becker's device each contain a set of tapered jaws. The lineman inserts the cable ends through apertures provided in each of the opposed ends of the device. After inserting suitable lengths of each cable into the device, the lineman draws the cables longitudinally away from the device. This action pulls the jaws into the tapered ends of the device's casing, thereby securely clamping the jaws on to the cable.
However, even modern automatic splice connectors still have numerous components, which require careful assembly and installation. Additionally, the cost of the raw materials of these automatic splice connectors remains high.
Accordingly, it would be desirable to provide a low cost automatic splice made with less raw material, fewer components and reduced assembly steps.
SUMMARY OF THE INVENTION
The present invention provides an automatic splice connector with an outer casing formed from a solid piece of conductive alloy. Thus, the automatic splice connector of the present invention generally includes a unitary casing having a longitudinal axis along which first and second ends of the casing taper conically toward the axis. The first end of the casing terminates at a first aperture and the second end of the casing terminates at a second aperture. The casing has an internal integral wall formed perpendicular to the longitudinal axis midway along the axial length of the casing, wherein the wall and the casing are contiguously formed as one piece.
The connector further includes a first cable gripping device disposed within the first end of the casing, a second cable gripping device disposed within the second end of the casing, a first biasing element disposed in the casing between the casing integral wall and an inner end of the first cable gripping device for urging the first cable gripping device along the axis towards the first aperture and a second biasing element disposed in the casing between the casing integral wall and an inner end of the second cable gripping device for urging the second cable gripping device along the axis towards the second aperture. A first plug is preferably secured in the first aperture and a second plug is preferably secured in the second aperture.
In a preferred embodiment, the casing is made of aluminum and the integral wall is formed with an axial through-hole to permit water flow between the first and second ends of the casing. Also, each of the first and second plugs preferably includes a tapered funnel guide fitted within a respective aperture and a pilot cup disposed within the funnel guide for receiving an end of a cable. The first and second plugs respectively temporarily prevent the first and second springs from advancing the first and second set of jaws towards the first and second apertures.
In addition, each of the first and second cable gripping devices are preferably in the form of a cooperating set of cable gripping jaws having a conically tapered outer surface conforming to the conically shaped first and second ends of the casing. Each of the first and second set of cable gripping jaws further preferably defines a semi-cylindrical inner surface bearing serrated teeth for gripping a cable.
The present invention further involves a method for manufacturing an automatic splice, which utilizes cold forming, or other similar process, to eliminate the need for seamless tube and improve manufacturability. Thus, the method according to the present invention generally includes the step of forming a unitary casing from a solid slug of metallic material, wherein the casing has a longitudinal axis, a first end terminating at a first aperture, a second end terminating at a second aperture longitudinally opposite the first aperture and an internal integral wall formed perpendicular to the longitudinal axis midway along the axial length of the casing, and wherein the wall and the casing are contiguously formed as one piece.
The method according to the present invention further includes the step of inserting a first biasing element within the first end of the casing, inserting a first cable gripping device within the first end of the casing such that the first biasing element is disposed between the casing integral wall and an inner end of the first cable gripping device for urging the first cable gripping device along the axis towards the first aperture. A second biasing element is then inserted within the second end of the casing and a second cable gripping device is inserted within the second end of the casing such that the second biasing element is disposed between the casing integral wall and an inner end of the second cable gripping device for urging the second cable gripping device along the axis towards the second aperture. The first and second ends of the casing are then mechanically deformed to form first and second ends that taper conically toward the longitudinal axis. The assembly is complete by securing first and second plugs in the respective first and second apertures.
The casing is preferably formed from a solid slug of aluminum, or other electrically conducting material, using a cold-forming process. The method for forming the casing further preferably includes the step of forming an axial through-hole in the integral wall to permit water flow between the first and second ends of the casing.
In a preferred embodiment, the unitary casing is formed by providing an elongate solid slug of metallic material, inserting a tool along the longitudinal axis in opposite axial ends of the slug to form the casing having respective axial bores formed in opposite ends thereof and stopping the tool short of forming a continuous axial bore in the casing, thereby leaving the internal integral wall in the casing.
A preferred form of the automatic splice, as well as other embodiments, objects, features and advantages of this invention, will be apparent from the following detailed description of illustrative embodiments thereof, which is to be read in conjunction with the accompanying drawings.