| 摘要 |
PURPOSE:To detect the water level in a bath tub by a simple constitution, without cumbersome operation, by providing a detecting device, which detects impedance that is varied with the water level in the bath tub, in a water-level detecting part. CONSTITUTION:A draining hole 5 is provided at the bottom part of a bath tub 6, and the draining hole 5 is closed by a water stop 7 and the water is stopped. Detecting lines 9a and 9b are fixed by holding tools 8a and 8b, which are connected to the upper and lower ends of the detecting lines 9a and 9b, so that a constant interval is provided. A connecting wire 10 connects the water stop 7 and the holding tool 8b so that they are freely removed. A water-level detecting part 9 is fixed by a fixing metal 11a, which is provided at the upper part of the bath tub 6, and a fixing metal 11b, which is provided at the holding tool 8a, so that the part 9 can be freely attached and detached. The change in resistance value R1, which is yielded by the change in water level in the bath tub 6 between the detecting lines 9a and 9b, is measured as follows: CMOS inverter elements 14 and 17, a resistor 15, and capacitor 16 are connected to the other end of a signal line 12, to one end of which the detecting lines 9a and 9b are connected; an oscillating circuit is formed in this way; and the oscillating frequency measured. |
