| 摘要 |
PURPOSE:To obtain an electric instantaneous water heater, which has high thermal efficiency and gives no shock of electricity, by a method wherein the secondary winding of a step-down transformer is also turned ON in response to the turning-ON of a tap so as to apply the secondary voltage of the transformer to an electric heating pipe connected in series on the upstream side of a tap pipe. CONSTITUTION:A step-down transformer 10 to transform high commercial supply voltage to low voltage of several volts, an electric heating pipe 20, which is connected in series on the upstream side of a tap 4 pipe and at the same time to which the secondary voltage of the transformer 10 is applied, and a switch to turn ON and OFF the primary winding of the transformer 10 in response to the turning-ON and -OFF of the tap 40 are provided. In other words, an electric instantaneous water heater, which has high thermal efficiency and is simple, can be obtained, because water flows directly through the electric heating pipe 20. In addition, no fear of being given the shock of electricity exists, because the voltage applied to the electric heating pipe is only several volts. Furthermore, because the whole electric heating pipe acts as a heat generating source, no fear of disconnection occurs even when a crack or the like develops on some portion of the electric heating pipe, resulting in facilitating the maintenance and management of the titled water heater. |
