SYSTEM FOR DETECTING MISSING VENT TUBES ON A BOTTLE FILLING APPARATUS

摘要

An apparatus for detecting the absence of a metal vent tube (28) from a bottle filling machine (10) comprises a nozzle (52) that produces a stream (56) of electrically conductive liquid which strikes the vent tube. A solenoid valve (62) controls the flow of liquid to the nozzle and is activated by a control signal from the controller of the bottle filling machine. The apparatus also includes a generator (66) which produces a signatured signal that is applied to the nozzle. A detector circuit has an input coupled to the frame of the bottle filling machine for detecting whether the signatured signal is present in the frame due to conduction from the vent tube. The detector responds to a failure to detect the signatured signal at the input by producing an output signal which indicates the absence of the vent tube. The controller responds to the detector output signal by shutting down the bottle filling machine until corrective action is taken.