| 摘要 |
PURPOSE:To enhance reliability by transmitting the detection signal of the number of rotations of a wheel from the transmission part provided to a frame by a wireless system to receive the same by a main body case and operating a running speed to display the same. CONSTITUTION:When a bicycle 1 is allowed to run, the magnet 4 of a front wheel 2 is detected by the lead switch 10 of a sensor case 8 and this detection signal is transmitted to a transmission antenna 12 through a transmission circuit part 11. When the transmission signal is received by a receiving antenna 20, in a main body case 19, a wheel number-of-rotation signal is demodulated by the receiving signal from said antenna 20 to be inputted to a microcomputer and a running speed is calculated to be displayed on a display device 22. By this method, reliability can be enhanced. |
