Global to push GA events into
skip to main content

Title: Instrument for measurement of vacuum in sealed thin wall packets

An instrument is disclosed for the measurement of vacuum within sealed packets, the packets having a wall that it can be deformed by the application of an external dynamic vacuum to an area thereof. The instrument has a detector head for placement against the deformable wall of the packet to apply the vacuum in a controlled manner to accomplish a limited deformation or lift of the wall with this deformation or lift monitored by the application of light as via a bifurcated light pipe. Retro-reflected light through the light pipe is monitored with a photo detector. A change (e.g., a decrease) of retro-reflected light signals the wall movement such that the value of the dynamic vacuum applied through the head be to achieve this initiation of movement is equal to the vacuum within the packet. In a preferred embodiment a vacuum plate is placed beneath the packet to ensure that no deformation occurs on the reverse surface of the packet. A vacuum can be applied to a recess in this vacuum plate, the value of which can be used to calibrate the vacuum transducer in the detector head. 4 figs.
Inventors:
; ;
Issue Date:
OSTI Identifier:
46325
Assignee:
Martin Marietta Energy Systems, Inc., Oak Ridge, TN (United States) PTO; SCA: 440800; PA: EDB-95:078620; SN: 95001384536
Patent Number(s):
US 5,406,831/A/
Application Number:
PAN: 8-130,261
Contract Number:
AC05-84OR21400
Resource Relation:
Other Information: PBD: 18 Apr 1995
Research Org:
Lockheed Martin Energy Syst Inc
Country of Publication:
United States
Language:
English
Subject:
44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; VACUUM GAGES; DESIGN; MEASURING METHODS; CALIBRATION; VISIBLE RADIATION; PHOTODETECTORS