| 摘要 |
In a scum removing apparatus including a suction source, a suction pipe having one end communicating with the suction source and the other free end positioned above the surface of scum to suck the scum and apply water to the sucked scum in the vicinity of the free end, and a scum separator provided at an intermediate portion of the suction pipe, a device for detecting the level of the scum surface relative to the free end of the suction pipe. The detecting device comprises a pair of electrode rods provided on the outer periphery of the free end of the suction pipe and projecting from the pipe end by a suitable length, and means for detecting variations in the electric resistance between the electrode rods. The electrode rod comprises a tube having accommodated therein a slider slidingly projectable from the front end of the tube and slidingly retractable into the tube. The slider is supported by a spring in its retracted position within the tube and connected to means for pushing out the slider from the front end of the tube against the action of the spring. |
