| 摘要 |
<p>An instantaneous water heater 10 has a housing 12 defining a chamber 16, a water inlet 24 and outlet 26 and a phase change material 30 (PCM) such as paraffin wax to transfer heat to/from water contained in or passing through the chamber. Water passing through the chamber can be heated by a heating element 32b before leaving the chamber through a tubular outlet 28 that leads to the water outlet. Ideally, a thermally conductive member 14 made of copper may be placed so as to enclose the PCM between a peripheral side wall 22 of the housing and the member. The member can include thermally conductive extension members (134, figure 2) such as annular fins to improve heat transfer between the PCM and the water. The extension members may also be cylindrical or rectangular parallelepiped in shape (figures 3-4) and be evenly spaced about the chamber. The water heater is preferably used in a shower whereby the PCM has a phase transition temperature equal to a safe maximum user showering temperature. This means that overheating of stationary water in the chamber by the element is prevented by the PCM, thereby protecting subsequent shower users from scalding.</p> |
