Loading patent…
AssigneeDeutsche Forschungs- und Versuchsanstalt fur Luft- und Raumfahrt e.V.
InventorRichard Schodl
Estimating the term…
This disclosure relates to an apparatus for measuring flow rates in gas sams and includes an optic component and an electronic component. The optic component starts with a focussed laser beam which is passed through a beam splitting prism so as to define two partial beams which, in turn, pass through a lens system so as to have two adjacent remote focal points. Particles in the gas stream passing through the focal points, which are located therein, reflect light in the form of reflected light beams which pass through a further lens system to pulse generators which, when actuated, generate a start pulse and a stop pulse with these pulses controlling the formation of a saw toothed wave controlling the amplitude of the generated wave, and the generated wave being directed to binary converter means and collector means which, in conjunction with an oscilliscope provides a visual wave having an amplitude indicative of a flow rate. The beam splitter is rotatable so as to selectively position one of the focal points within the gas stream with respect to the other so as to obtain a directional vector of the flowing gases.
Measuring device for the measurement of flow rates of fluids by determining the rate of movement of optically detectable particles present in the fluid flow, said device comprising a light source means for emitting a focussed beam, a beam splitter for receiving said beam and dividing said beam into two generated partial beams, a first lens system in the path of said partial beams for focussing the two partial beams in a fluid test volume at closely adjacent focussing points, a photoelectric converter system, a second lens system for directing light beams reflecting from particles in the test fluid to said photoelectric converter system, means for rotating said beam splitter to selectively change the direction of an imaginary straight line passing through said two focussing points, said photoelectric converter system including two photoelectric converters, said second lens system having means for imaging light beams reflected from particles at said two focussing points separately on respective ones of said photoelectric converters, said second lens system including a dual hole diaphragm for receiving reflected light beams from said two focussing points, and means for adjusting said diaphragm simultaneously with the rotation of said beam splitter.
Dependencies are inferred from the claim text.