Photoelectric apparatus for continuously monitoring the quality of a flowing particulate material in respect of its granularity and purity

Claim 1

APPARATUS FOR THE AUTOMATIC CONTINUOUS MONITORING OF THE QUALITY OF DRY PARTICULATE MATERIAL COMPRISING A SAMPLE HOLDER, A TRANSPARENT WINDOW IN THE SAMPLE HOLDER MEANS LEADING TO THE SAMPLE HOLDER FOR CONTINUOUSLY COLLECTING PARTICULATE MATERIAL FROM A SUPPLY THEREOF, OPERABLE VALVE MEANS CO-ACTING WITH THE COLLECTING MEANS TO CONSOLIDATE THE COLLECTED MATERIAL TO A PREDETERMINED UNIFORM DENSITY SO THAT IT PASSES WITHOUT CONSEQUENT CHANGE IN GRANULARITY ACROSS THE TRANSPARENT WINDOW, A REFLECTING SURFACE OF A CHARACTERISTIC APPROVED AS A STANDARD FOR COMPARISON, A LIGHT SOURCE CONSISTING OF A SINGLE LIGHT BEAM, A ROTATING BEAM DEFLECTING MEANS DISPOSED TO RECEIVE LIGHT FROM THE LIGHT SOURCE AND OPERABLE TO PROJECT THAT LIGHT ALTERNATELY ON TO THE STANDARD SURFACE AND, THROUGH THE TRANSPARENT WINDOW, ON TO THE MATERIAL IN THE SAMPLE HOLDER, A COMMON PHOTOCELL WHICH RECEIVES A SCATTERED REFLECTION OF THE LIGHT OF THE SINGLE BEAM OF LIGHT ALTERNATELY FROM THE STANDARD SURFACE AND THE MATERIAL, PHASE SENSING MEANS WHICH RELATES THE PARTS OF THE PHOTOCELL OUTPUT TO THE RESPECTIVE REFLECTING SURFACES, MEANS CONTROLLED BY THE OUTPUT OF THE PHOTOCELL AND THE PHASE SENSING MEANS TO EFFECT AN INDICATION OF A DIFFERENCE IN THE RELATIVE VALUES OF THE REFLECTED LIGHT, AND COMPRISING A SHUTTER ELEMENT ARRANGED IN THE PATH OF THE LIGHT REFLECTED FROM ONE OR OTHER OF THE REFLECTING SURFACES AND ADJUSTABLE SO AS TO MASK THAT LIGHT TO A VARIABLE EXTENT, MOTOR MEANS FOR ADJUSTING SAID SHUTTER ELEMENT AND CONTROLLED IN ACCORDANCE WITH THE OUTPUT OF THE PHOTOCELL AND OF THE PHASE SENSING MEANS TO MOVE THE SHUTTER ELEMENT IN A DIRECTION WHICH TENDS TO RESTORE EQUALITY IN THE LIGHT RECEIVED FROM THE TWO REFLECTING SURFACES, AND INDICATOR MEANS OPERATIVELY ASSOCIATED WITH THE SHUTTER ELEMENT TO INDICATE THE MOVEMENT AND POSITION THEREOF, AND SIGNAL MEANS ASSOCIATED WITH THE SHUTTER ELEMENT SO AS TO BE ACTUATED BY MOVEMENT OF THE SHUTTER ELEMENT TO EXTREMITIES OF A PREDETERMINED RANGE.