| 摘要 |
A leak detecting device for identification of can tops and similar workpieces with leak holes has a compressed gas supply chamber providing a source of compressed gas for testing the workpieces for leaks. An acoustic testing chamber is mounted adjacent the gas supply chamber. A sealing press is provided between the chambers for holding a workpiece in a gas tight manner so that one side of the workpiece faces the compressed gas supply chamber in a gas tight relationship and the other side of the workpiece faces the acoustic testing chamber in a noise tight relationship. A valve is provided on the compressed gas supply chamber and is operable to admit compressed gas from the gas supply chamber to the side of said workpiece facing the compressed gas supply chamber. An ultrasonic microphone is disposed within the acoustic testing chamber and is adapted for detecting gas noise created by gas passing through a leak hole in the workpiece. A gas venting port is disposed adjacent the periphery of the microphone and communicates with a labyrinth baffle with a gas vent passage leading to the atmosphere. An electrical control receives gas leak noise signals from the microphone after the valve has opened and rejects workpieces giving off gas leak noise signals. |
