Cut-off chamber of a lightning protector
AssigneeDelle-Alsthom
InventorRobert Deville
Life of this patent
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Abstract
Cut-off chamber of a lightning protector, characterized in that on the one hand, it comprises a wall made of a porous ceramic substance, ensuring the discharge and the cooling of the gases at the periphery of the chamber, at the time of the ignition of an arc between two elctrodes combined in that chamber and that on the other hand, a means for reinforcing the dielectric strength of the wall is arranged perpendicular to the zones subjected to the highest potential gradients.
Claims15
Cut-off chamber defined by two adjacent walls having a periphery, a central region, electrodes located in said central region, and zones of high potential gradients around said electrodes, characterized in that said walls are made of a porous ceramic material ensuring the discharge and the cooling of the gases at the periphery of the chamber at the time of the flash of an arc between said electrodes, said porous ceramic material comprising a substance of higher dielectric strength at said zones than at the periphery of said walls.
In a blow-out lightning protector of the type including a stack of chambers formed by a stack of insulating disks of porous ceramic material, each disk having a planar wall perpendicular to the longitudinal axis of the stack and a peripheral upstanding rim so that the rims act as spacers to form the stack of chambers, each chamber containing a pair of separated electrodes for supporting an arc therebetween and spaced inwardly from the rim, the porosity of the ceramic material being sufficient to pass and cool gases formed upon the occurrence of an arc between the electrodes, and wherein very high potential gradients occur in a zone of the planar wall between electrodes which are in adjacent chambers and which are on opposite sides of the wall,
- the improvement wherein said zone of very high potential gradients comprises a non-porous material of higher dielectric strength than said porous ceramic material, thereby preventing electrical breakdown of said zone while simultaneously permitting discharge and cooling of gases by the remainder of the disk not included in said zone.
Dependencies are inferred from the claim text.