Patent ID: 8627728

Claim:
A flow meter, comprising: a cylinder having a cylinder length, a cylinder exterior, a cylinder centerline, a cylinder first end and a cylinder second end, said cylinder having a cylinder axis at said cylinder centerline along said cylinder length, said cylinder having a first end connector and a second end connector, said cylinder composed of non-ferrous material; a ferrous floating internal piston freely slidable in said cylinder between said cylinder first end and said cylinder second end, said piston having a piston length; a cylindrical ring slidably positioned about and closely encircling said cylinder exterior, said cylindrical ring magnetically coupled to said ferrous floating internal piston, said cylindrical ring maintained substantially concentric with said cylinder axis; an absolute linear digital encoding transducer having a transducer length and transducer axis, said transducer axis substantially parallel to said cylinder axis, said transducer length generally equivalent to said cylinder length; a coupling arm having a coupling arm first end and a coupling arm second end, said coupling arm integrally affixed to said cylindrical ring at said coupling arm first end and maintained generally perpendicular to said cylinder axis, said coupling arm having a magnetic section at said coupling arm second end, said magnetic section having a magnetic field interacting with said linear digital encoding transducer; a valve system having a fluid input, having a fluid output, in fluid communication with said first end connector and in fluid communication with said second end connector, said valve system switchably operable among a first position and a second position, said first position connecting said fluid input and second end connector and connecting said first end connector with said fluid output and said second position connecting said fluid input and said first end connector and connecting said second end connector with said fluid output; and a position-determining controller adapted to determine a plurality of the positions of said coupling arm relative to said linear digital encoding transducer, recording said plurality of positions and an associated time for said plurality of positions, determining the speed and direction of movement of said coupling arm relative to said linear digital encoding transducer as a function of difference in said position between said associated times; and a valve system controller adapted to cause said valve system to reciprocate said ferrous floating internal piston between said cylinder first end and said cylinder second end at least when said piston approaches either said cylinder first end or said cylinder second end.