Electrical insulator apparatus and method of manufacturing the same

Abstract

An electrical insulator apparatus and method of manufacturing an electrical insulator apparatus includes a core strength member which is positioned at least partially within at least one end-fitting. A thermoplastic exterior body having a plurality of spaced fins is injection-molded over the core strength member and at least partially over the at least one end-fitting. The core strength member is attached to the at least one end-fitting without a mechanical compression to the at least one end-fitting and without an adhesive between the core strength member and the at least one end-fitting. One or more mechanical upset structures formed on the at least one end-fitting prevent movements of the injection molded thermoplastic exterior body relative to the at least one end-fitting.

Description

FIELD OF THE DISCLOSURE[0001]The present disclosure is generally related to overhead distribution and transmission insulators and more particularly is related to an electrical post insulator apparatus and methods of manufacturing the same.BACKGROUND OF THE DISCLOSURE[0002]Insulators are used with electrical transmission and distribution systems to isolate and support electrical conductors above the ground for overhead power distribution and transmission. In power distribution systems, the most common insulator types are Pin-type and Post type insulators mounted on wood cross-arms to mechanically support the line conductors. These insulators are primarily designed for static loads but may be subject to dynamic loads, such as wind induced vibrating conductors or heavy objects falling on the line such as tree branches; therefore, they must withstand complex loads with compressive, cantilever, tensile and rotational force components. Pin-type insulators were developed in the nineteenth ...

AI Technical Summary

Benefits of technology

The present invention provides an improved electrical insulator apparatus which has a stronger core and a more secure attachment between the core and the end-fitting without using adhesive or mechanical compression. The apparatus has a thermoplastic exterior body with a plurality of spaced fins that is injection molded over the core strength member and at least partially over the end-fitting. The end-fitting has a vertical and rotational mechanical upset structure that prevents the injection molded thermoplastic exterior body from moving vertically or rotationally relative to the end-fitting. The technical effect of this invention is to provide a stronger and more secure electrical insulator apparatus that withstands higher temperatures and provides better electrical insulation.

Problems solved by technology

These insulators are primarily designed for static loads but may be subject to dynamic loads, such as wind induced vibrating conductors or heavy objects falling on the line such as tree branches; therefore, they must withstand complex loads with compressive, cantilever, tensile and rotational force components.

Non-ceramic insulators have grown in usage to be the preferred insulator for many post applications due to light weight, high strength, flexibility and resistance to impact; however, they have a high per unit cost when compared to conventional ceramic units.

The current manufacturing methods require substantial machining, labor and equipment or materials to permanently attach the insulator components in the assembly process.

The compression crimping method, though effective and preferred over other methods for cost advantages, is nonetheless costly, time-consuming and alters the surface of the fiberglass core.

Another disadvantage of the crimping method is the creation of micro-fractures in the core material which can jeopardize the strength rating.

Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.

Images