This invention relates to battery chargers.
Low voltage rechargeable batteries are used in many appliances, for example electric dry shavers. The appliance may include at least one rechargeable battery and an integral charger comprising a charging circuit including AC input terminals, a transformer, and a full wave current rectifier. A pilot lamp is desirably connected for energization during charging to indicate normal operation of the charging circuit. Extinction of the lamp signals some malfunction of the charging operation, such as lack of mains voltage or poor contacts.
In a compact hand-held appliance, such as an electric dry shaver, space and weight are strictly limited. Consequently the batteries, transformer, current rectifier and even the charging terminals for connection to the AC mains are designed to minimum dimensions and weight. The power output of the transformer is thus very limited and must be used with maximum efficiency to permit recharging to be accomplished within an acceptable short time period.