Fluidic type leak testing machine

Abstract

This invention relates to an improved apparatus for effecting the high speed testing of hollow articles or containers for leakage. The apparatus includes a normally closed charge valve and a normally open test valve connected in series between a regulated source of pressurized air and the container. A fluidic start signal sets a first fluidic flip flop device to actuate the charge valve to supply pressurized air to the container and energize a first fluid time delay unit which determines the time that the container is to be filled with air. When the first time delay unit times out, it actuates the test valve to connect the container through a flow meter to a test source of pressurized air to measure the flow rate through the container in the event that any leakage is occuring. The output from the first time delay unit also starts a second fluid time delay unit which determines the test period. If the container is acceptable, the second time delay unit resets a second fluidic flip flop unit, turns on an 'accept' light, pulses a counter to record the number of good containers, and resets the first flip flop. In the event that the flow rate exceeds a predetermined value, the flow rate meter actuates a solenoid actuated valve such that the second time delay unit sets the second flip flop and turns on a 'reject' light.