Electrically insulating plastic element for an electrical switching device, especially for use as the blast nozzle of a gas-blast switch
AssigneeSprecher & Schuh AG
InventorRudolf Graf
Life of this patent
Estimating the term…
Abstract
A plastic mass of a blast nozzle contains a filler which is at least partially composed of powder of one or more metals. The proportion of metal powder amounts to at most 30 percent by weight, preferably 5 to 15 percent by weight. As the filler there is particularly suitable, alone or in combination, the metals of tungsten, copper, aluminum and iron. The electrically conductive filler prevents penetration of the electromagnetic radiation emanating from the arc into the interior of the blast nozzle, resulting in an appreciable reduction in nozzle burn-off.
Claims10
An electrically insulating blast nozzle for a gas-blast switch, comprising:
- a plastic material forming said electrically insulating blast nozzle;
- said plastic material of the blast nozzle containing a filler which essentially prevents penetration of electromagnetic radiation into the interior of the plastic material of the blast nozzle;
- said filler consisting of a powder of at least one metal selected from the group consisting essentially of tungsten, copper, aluminum and iron;
- and
- the proportion of the metal powder amounting to at most 30% by weight.
The electrically insulating blast nozzle as defined in calim 6, wherein:
- said moldable plastic contains a modified tetrafluoroethylene and ethylene copolymer having a proportion of at least 60% by weight tetrafluoroethylene.
Dependencies are inferred from the claim text.