| 摘要 |
A heating apparatus 10 comprises an air inlet 14, at least one air outlet 18, an impeller (64, fig.3), a motor 68 for rotating the impeller to draw air through the air inlet, a user interface 24, 26, 28, 30, 32, 34 for allowing a user to select a rotational speed of the motor from a user selectable range of values, and at least one heater assembly (104, fig.4) comprising at least one positive temperature coefficient (PTC) heating element 106 for heating air passing from the air inlet to a respective air outlet. The magnitude of a current drawn by the at least one heater assembly is detected, and the rotational speed of the motor is controlled independently from the rotational speed selected by the user depending on a characteristic of the current drawn by the at least one heater assembly. Preferably, the heating apparatus takes the form of a portable fan heater for creating a warm air current in a room, office or other domestic environment. |
