Abstract: This invention relates to a power converter (1) comprising a converter input (3), a converter output (5), a power factor correction (PFC) stage (7) and an isolation stage (9). The PFC stage (7) is implemented by way of a buck PFC with low side drive and low side current sensing, There is provided a third stage, an intermediate buck pre-regulation stage (11), intermediate the buck PFC stage (7) and the isolation stage (9), Control of the power converter output voltage is achieved by varying the duty cycle of the intermediate buck pre-regulation stage (11) and therefore the isolation stage (9) may be an unregulated stage operated as a fixed DCDC voltage converter. The isolation stage (9) is operated as a 50%-50% duly cycle double ended stage. The configuration of power converter allows for a relatively inexpensive, highly efficient converter with 90%+ efficiency and simplified control.

Abstract: This invention relates to a power converter (1) comprising a converter input (3), a converter output (5), a power factor correction (PFC) stage (7) and an isolation stage (9). The PFC stage (7) is implemented by way of a buck PFC with low side drive and low side current sensing, There is provided a third stage, an intermediate buck pre-regulation stage (11), intermediate the buck PFC stage (7) and the isolation stage (9), Control of the power converter output voltage is achieved by varying the duty cycle of the intermediate buck pre-regulation stage (11) and therefore the isolation stage (9) may be an unregulated stage operated as a fixed DCDC voltage converter. The isolation stage (9) is operated as a 50%-50% duly cycle double ended stage. The configuration of power converter allows for a relatively inexpensive, highly efficient converter with 90%+ efficiency and simplified control.

Abstract: A rupture type openable beverage container lid in the form of a beverage can lid (10) comprises an opening tab (12) mounted to a centrally positioned rivet (14) and a shield (16) lying against the inside surface (18) of the wall (20) of the lid (10). The tab (12) is also mounted to be swivelled about the rivet (14). The shield (16) is secured to the tab (12) via a shaft (38) passing snugly though a bore along the rivet (14). The shaft (38) is secured against release of gas at its inner end (38.4). The tab (12) and the shield (16) lie in alignment with one another with the shield (16) being swivellable in conjunction with the tab (12) to close off an opening formed in the lid (10) as conventionally formed by way of a rupture type action.