Register CIPO Patent
Document Number 02651721
Status In Force
Filing Date 2007-05-04
Open to Public Date 2007-11-15
Publication Date 2007-11-15
Grant Date 2011-04-12
  • Knowles, Steven M.
  • Klipstein, Donald L.
  • Appler, Paul C.
  • Brass, Jack E.


A manifold gauge set has at least one sight glass window for viewing contents of a refrigeration system or an air conditioning system being serviced. The window may be non-planar to achieve an appearance that varies with the presence or absence of liquid. Such a non-planar window may be in the form of a dome, prism, or a fresnel lens. The gauge set may have a second light transmissive window to allow light to illuminate system contents being viewed. A light source may be provided to illuminate system contents being viewed. The light source may provide light through the same window that is used for viewing contents. A diffuser may be provided with a second window to achieve an illuminated background for viewing system contents. Similar configurations may be used in standalone sight glasses, vacuum pumps, and recovery machines.

IPC Classes  ?

  • G01N 21/90 - Investigating the presence of flaws, defects or contamination in a container or its contents
  • F25B 45/00 - Arrangements for charging or discharging refrigerant
  • G01D 11/26 - Windows; Cover glasses; Sealings therefor
  • G01F 23/02 - Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by gauge glasses or other apparatus involving a window or transparent tube for directly observing the level to be measured or the level of a liquid column in free communication with the main body of the liquid
  • G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
  • G01L 19/16 - Dials; Mounting of dials
  • G01N 21/91 - Investigating the presence of flaws, defects or contamination using penetration of dyes, e.g. fluorescent ink
  • G01N 21/64 - Fluorescence; Phosphorescence