Pneumatic type spraying apparatus for spraying treating fluid e.g. weed killer, to vine, has indicating unit indicating passing state or non-passing state on electrical plane between conducting pipe portions

摘要

The apparatus has a supply pipe (28) circulating treating fluid with non-zero conductivity and arranged between a tank and an ejection unit i.e. nozzle. A control unit (40) controls flow of fluid on a level of the supply pipe. The control unit has two electrically conducting pipe portions (42, 44) and an electrically insulating pipe portion (46). An indicating unit (48) indicates passing state or non-passing state on an electrical plane between the conducting pipe portions, where the non-passing state corresponds to sealed state of the supply pipe.