| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a filling sensor capable of reliably detecting not only a state of being completely filled with a fluid but also a state of a level of the fluid having approached.SOLUTION: A filling sensor 1 for detecting a filling state of grout 51 comprises a first LED 5 and a second LED 7, and a first phototransistor 6 and a second phototransistor 8 for respectively detecting a light beam emitted from the first LED 5 and the second LED 7 and reflected by the grout 51. The filling sensor further comprises a transparent plate 9 with which the first phototransistor 6 and the first LED 5 are covered. The filling state of the grout 51 is determined by using a detection signal of the first phototransistor 6 covered with the transparent plate 9 and a detection signal of the second phototransistor 8 not covered with the transparent plate 9.</p> |
