Abstract: A pipe tool comprises a head mounted on a shaft. The head has a primary channel having a circular profile of a primary channel diameter and a secondary channel having a circular profile of a secondary channel diameter. The secondary channel diameter is smaller than the primary channel diameter. The head has an intermediate wall having an intermediate wall outside surface defining an inside boundary of the primary channel, and the intermediate wall has an intermediate wall inside surface defining an outside boundary of the secondary channel. An intermediate wall gap passes between the primary channel and the secondary channel. An intermediate wall outside corner is disposed on the intermediate wall gap. An outside wall has an outside wall inside surface bounding the external periphery of the primary channel.

Abstract: A driving circuit for driving an electroluminescent lamp is disclosed. The driving circuit includes an alternating current (AC) voltage generator for providing at an output an AC output voltage waveform for driving an electroluminescent lamp and a controller for controlling the phase and polarity of the AC output voltage waveform. The controller is operable to reverse the phase and polarity of the AC output voltage. In one embodiment, the AC voltage generator includes a transformer.

Abstract: A cold-cathode fluorescent lamp, comprising a sealed lighting enclosure provided with a phosphor coating on at least part of an inner surface thereof the lighting enclosure. An electrode is provided juxtaposed a region of the inner surface of the lighting tube, the electrode energisable from an external source of energy via an electric lead supporting the electrode, and positioned adjacent the main ionisation region within the lighting enclosure. The phosphor is to be excited by radiation to be generated inside the lighting tube by electric discharge from the electrode to provide visible radiation. At least part of the surface(s) of that portion of the electrode proximal most to the ionisation region are overlaid by a cap made from a high heat resistive and non conductive material.