Apparatus for measuring particles in liquids

Claim 1

AN APPARATUS FOR TESTING A FLUID FOR PARTICLE INCLUSIONS WHEREIN THE PARTICLES HAVE SIZES IN PRESELECTED RANGES AND WHEREIN THE PARTICLES ARE NORMALLY DISTRIBUTED IN PREDETERMINED RATIOS BETWEEN SAID RANGES, SAID APPARATUS INCLUDING THE COMBINATION OF, MEANS FOR TRANSMITTING PULSES OF ULTRASONIC ENERGY INTO SAID FLUID, SAID MEANS BEING EFFECTIVE TO RECEIVE ULTRASONIC ENERGY REFLECTED FROM PARTICLES CONTAINED IN SAID FLUID AND PRODUCE EQUIVALENT ELECTRICAL SIGNALS, GATING MEANS COUPLED TO THE FIRST MEANS FOR ALTERNATELY BLOCKING AND PASSING SAID SIGNALS, SAID TRANSMITTING MEANS AND SAID GATING MEANS PROVIDING A BEAM OF ULTRASONIC ENERGY IN WHICH TEST ZONES OF DIFFERENT VOLUMES ARE ESTABLISHED ALONG ITS LENGTH, SAID VOLUMES BEING IN APPROXIMATELY THE SAME RATIOS AS THE NUMBERS OF SAID PARTICLES AND IN SAID SIZE RANGES, AND SEPARATE COUNTING MEANS FOR EACH OF SAID TEXT ZONES, EACH OF SAID COUNTING MEANS BEING COUPLED TO THE GATING MEANS FOR COUNTING THE ECHOES CORRESPONDING TO THE ZONES AND HAVING AMPLITUDES CORRESPONDING TO THE PARTICLES HAVING SIZES WITHIN THE CORRESPONDING RANGES.