Electric coffee maker with through-flow water heater - prevents deposition of lime scale by applying ultrasonic oscillations in conjunction with valve movements

摘要

The water heater comprises a vessel (1) containing an electric heating element, with a piezoelectric ultrasonic oscillation generator (10) also incorporated in this vessel (11), to prevent build-up of hard water deposits. The generator projects into the interior of the vessel (1) of it is attached to the inside or outside wall of the latter. Pref. the ultrasonic oscillation generator is switched 'ON' and 'OFF' in conjunction with opening and closing of the valve (15) controlling the flow of water from the through-flow heater to the infusion point (2).