Sealed package testing appts. - applies vacuum to chamber around package and monitors package distortion with piezoelectric strain gauges

摘要

Appts. for testing the seal integrity of pressure wrappings is described in which a compartment for the wrapping under test has a control rod (5) communicating with the exterior of the compartment. In use an outer bell (1) forms a sealed envelope around the compartment. The space between the bell (1) and compartment wall (6) and inside the compartment itself is then evacuated over conduit (4). Piezo electric strain gauges (8) send analysis signals to processing stages (15 and 16).