Arc-extinguishing composition and articles manufactured therefrom

Abstract

An arc-interrupting compound, such as melamine, and to a method of extinguishing an arc by disposing the composition along the path of the arc, for contacting the arc. In one embodiment, the binder, or at least a portion of the binder, is a polymer that contains a functional group that binds to a coupling agent that is included in the arc-extinguishing composition. The coupling agent ties the polymeric binder to the arc-extinguishing compound, e.g., melamine, to provide new and unexpected physical strength and stability to the composition. In this embodiment, the molded composition, including the arc-interrupting compound coupled to the binder, maintains excellent arc-interrupting capability, while providing chemical stability and electrical insulating properties as well as unexpected physical strength.

Description

FIELD [0001] The present invention relates to arc-quenching materials and articles fabricated therefrom for high-voltage electrical devices and equipment such as circuit interrupters wherein, under certain conditions of operation, a high-voltage electrical arc is produced that is either desirably, or by necessity, quenched. More particularly, the present invention relates to a composition to achieve arc-quenching and structural properties in devices such as circuit interrupters, high-voltage fuses, circuit breakers, and separable cable connectors. BACKGROUND AND PRIOR ART [0002] To provide effective circuit interruption in circuit interrupters, fuses, and the like, it is desirable to utilize an arc-quenching material or composition to quench and suppress arcing during electrical contact separation or fuse operation. Of necessity, the arc-quenching materials should include characteristics and properties sufficient for the particular application so as to be effective in quenching arcs...

AI Technical Summary

Benefits of technology

[0010] In brief, the present invention is directed to a new and improved arc extinguishing composition including, a new and improved binder for compositions containing an arc-interrupting compound, such as melamine, and to a method of extinguishing an arc by disposing the composition along the path of the arc, for contacting the arc. In one embodiment, the binder, or at least a portion of the binder, is a polymer that contains a functional group that binds to a coupling agent that is included in the arc-extinguishing composition. The coupling agent, which may be a polymer that is compatible with the binder, contains a functional group that binds to the arc-extinguishing compound to tie the polymeric binder to the arc-extinguishing compound, e.g., melamine, to provide new and unexpected physical strength and stability to the composition. In this embodiment, the molded composition, including the arc-interrupting compound coupled to the binder, maintains excellent arc-interrupting capability, while providing chemical stability and electrical insulating properties as well as unexpected physical strength.

[0011] In other embodiments of the arc-extinguishing compositions and articles described herein, the melamine or other arc-extinguishing compound provides unexpectedly better results when incorporated into the composition in finely divided form; and improved results are provided by combining a plasticizer for the polymeric binder.

[0012] At least three embodiments of the arc-quenching materials and articles are described herein—each embodiment providing improved mechanical properties and / or arc-extinguishing results either alone or in combination with one or both of the other embodiments. Each of these three individual embodiments can be included alone in the materials and articles described herein or any two or three of these embodiments can be combined to further improve the materials and articles described herein.

Problems solved by technology

The action of the gases produced by the trailer and / or liner on the confined arc tends to deionize the arc and force its extinction.

Melamine and its related compounds have excellent arc-interrupting characteristics but suffer from extreme structural weakness, so that they cannot be molded or pressed into satisfactory structural shapes except in combination with a suitable binder.

Structural damage, i.e., cracks have been found in prior art devices containing polyethylene as its primary binder material, and such damage is unacceptable in this art, since the break point allows another air space for the gases and arc to fill, thereby significantly lessening the arc-interrupting properties of the arc-interrupting device.

Further, failed arc extinguishing compositions that contain melamine usually fail because the pressure wave associated with the arc causes the composition to physically break before it has an opportunity to extinguish the arc.

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