Airline lubricator

Claim 1

IN A DEVICE FOR MIXING FLUIDS, A HOUSING HAVING A FIRST PASSAGE THERETHROUGH FOR FLOW OF A FIRST FLUID UNDER PRESSURE, MEANS FOR ESTABLISHING A LOWER PRESSURE OF SAID FLUID IN THE OUTLET END OF SAID PASSAGE THAN IN THE INLET END, A RESERVOIR CONTAINING A SECOND FLUID, PASSAGE MEANS CONNECTING SAID FIRST PASSAGE INLET END WITH SAID RESERVOIR TO PRESSURIZE THE FLUID THEREIN, A FEED TUBE HAVING AN INLET IMMERSED IN SAID SECOND FLUID AND HAVING AN OUTLET CONNECTED TO SAID FIRST PASSAGE OUTLET WHEREBY THE GREATER PRESSURE IN THE FIRST PASSAGE INLET FORCES THE SECOND FLUID THROUGH THE FEED TUBE TO SAID FIRST PASSAGE OUTLET, SAID TUBE HAVING A VISIBLE TRANSPARENT PORTION CONTAINING A FLOW ELEMENT MOVABLE BY FLUID FLOWING THROUGH THE TUBE TO DIFFERENT POSITIONS ACCORDING TO THE RATE OF THE FLOW THROUGH THE FEED TUBE, SAID TRANSPARENT PORTION HAVING BORE SECTIONS OF DIFFERENT TAPERS TO PROVIDE DIFFERENT RATES OF CHANGE OF RADIAL CLEARANCE AROUND SAID FLOW ELEMENT AS THE LATTER IS MOVED. .