Abstract: An isolating power supply for electrical equipment comprises a transformer having an input for a mains alternating current (AC) power supply, a rectifier by which the output of the transformer can be rectified, and a primary energy storage device for electrically smoothing the output of the rectifier. A switching device is provided which is electrically connected to the output of the primary energy storage device and which can be switched between a conducting state and a non-conducting state, and a secondary energy storage device is also provided which is electrically connected to the switching device. In use, when the switching device is in a non-conducting state, the primary energy storage device stores the output from the rectifier and the secondary energy storage device is electrically isolated from the primary energy storage device and supplies an electrical output to associated electrical equipment.

Abstract: A method of forming plastics sheets, comprises the steps of supporting a die (or substrate 12) between plastics sheets 36 in an enclosure, heating the plastics sheets 36 by infra-red heating element 28, evacuating air from the enclosure, and urging the plastics sheets 36 into contact with opposite faces of the die (or substrate 12) while maintaining a vacuum or a substantial vacuum between the plastics sheets 36. Apparatus for performing this method is also disclosed.

Abstract: An isolating power supply for electrical equipment comprises a transformer having an input for a mains alternating current (AC) power supply, a rectifier by which the output of the transformer can be rectified, and a primary energy storage device for electrically smoothing the output of the rectifier. A switching device is provided which is electrically connected to the output of the primary energy storage device and which can be switched between a conducting state and a non-conducting state, and a secondary energy storage device is also provided which is electrically connected to the switching device. In use, when the switching device is in a non-conducting state, the primary energy storage device stores the output from the rectifier and the secondary energy storage device is electrically isolated from the primary energy storage device and supplies an electrical output to associated electrical equipment.

Abstract: The method includes the step of applying a heat shrinkable plastics sleeve to at least that part of the object most vulnerable to decay. A meltable sealing solution, typically a bituminous substance, is provided between the heat shrinkable plastics sleeve and the object. The sleeve is heated so as to melt the sealing solution sufficiently for it to bond intimately to the wooden object and pressure is applied to the plastics sleeve. The sleeve may be extruded and the sealing solution may be applied to the internal surface of the sleeve as it is extruded. Pressure can be applied to the sleeve using pressure pads, which may be heated, or by a jet of hot air.

Abstract: A method in which a flexible outer barrier layer is applied to at least that part of the object most vulnerable to decay, a bituminous substance is provided between the outer barrier layer and the object, and the barrier layer is heated so as to melt the bituminous substance sufficiently for it to bond intimately to the wooden object. The barrier layer may be a heat shrinkable plastic film and may be a sleeve which is heat shrunk onto the object. The invention is particularly useful for protecting vulnerable parts of elongate wooden objects, such as fence posts or poles, from decay.