Patent ID: 7213464
Filing Date: 2007-05-08
Classification: G01L

Abstract:
1. A visually monitorable differential pressure detecting system for use in monitoring pressure differential between two different environments, said differential pressure detecting system comprising a balloon having a front reflective surface, said balloon being contained within a substantially rigid framework which presents with a transparent window on at least one side thereof, there being an opaque element on said transparent window; the inside of said balloon being, in use, exposed to one environment and the outside thereof being exposed to another environment; said front reflective surface being positioned near said opaque element on said transparent window, such that the reflection of said opaque element from said reflective surface of said balloon is viewable when said front reflective surface is a distance from the opaque element, but not visible when said front reflective surface is substantially in contact with or in contact with the opaque element on said transparent window; such that when the air pressure inside the balloon does not cause the balloon to expand such that the front reflective surface thereof is not substantially in contact with or in contact with the opaque element on the transparent window, the reflection of said opaque element from said reflective surface is viewable, and when the air pressure in said balloon causes the balloon to expand such that the front reflective surface is substantially in contact with or in contact with the opaque element, said reflection of said opaque element is prevented or hidden from view.