| 摘要 |
PROBLEM TO BE SOLVED: To make an electric power source switched automatically from a built-in battery to an external power source provided in an engine at the same time when a main switch of a vehicle is turned on, to make the electric power source turned off and display fade away automatically when not used, and to make a digital thermometer bright and easily visible even in a night when used. SOLUTION: This thermometer is provided with a sensor 1 for sensing various kinds of temperatures, a computing means 2 for calculating a temperature value based on a signal thereof, a display means 3 for displaying a value corresponding to an output signal of the means 2 as a temperature in response to a prescribed unit, an illumination means 4 having EL(electroluminescence) integrated with the display means 3, and a display unit switching means 5 operated by a user. The power source is switched to the external power source when an external electric power source signal is input from an external power source switching means 8 of the vehicle to the computing means 2. |
