Compact fluorescent lamp having a partitioned envelope

Abstract

The envelope of a fluorescent lamp is provided with a partition assembly of sheet metal or other rigid material that is inserted into the envelope and forces the art discharge to follow a tortuous path which is longer than the envelope, thus reducing the size of the lamp and providing a concentrated light source. The inherent tendency of the arc to bypass the partition by seeking and passing through small gaps or crevices between the envelope wall and the mating edges of the partition assembly is prevented by providing the longitudinal edges of the partition assembly with short laterally-extending flanges that are seated against or closely overlie the envelope wall. The resulting lengthening of the arc-leakage paths through such gaps or crevices creates a 'barrier' along the envelope-partition interface which cannot be breached by the arc. Short-circuiting of the arc around the end portion of the partition assembly is prevented by a diaphragm component comprising a transverse panel member that is secured to the partition assembly and has a peripheral flange that makes a snug fit with the side walls of the envelope. The diaphragm component can also comprise a compliant pad-like gasket of porous material that is held in nested relationship with the end portion of the partition assembly by retaining means.