Abstract: A high volume, low RPM, low noise, low wear and long life flowmeter uses inter-engaging double helical four-lobe rotors. The meter is made with ball bearings or bearingless. The double helical nature of the teeth provides no axial loads and no side loads or end loads, and uses true gear designs with very large pockets. A high contact ratio is provided with only four teeth, reducing and eliminating noise and pulsing output, increasing working volume and decreasing speed and wear.

Abstract: A fluid volumetric flowmeter has a wall plate forming a chamber and a fluid inlet, and a fluid outlet. Two rotors positioned within the chamber have intermeshing lobes and valleys for turning in the chamber as fluid flows from the inlet through the chamber to the outlet. An indicator housing is connected to the chamber. A response shaft is rotationally mounted in the housing, and an encoder disk rotates with the shaft. A first coupling is mounted on the rotor. A second coupling is mounted on the shaft for rotating the second coupling, the shaft, and the encoder disk in response to rotation of the rotors.

Abstract: A fluid volumetric flowmeter has a wall plate forming a chamber and a fluid inlet, and a fluid outlet. Two rotors positioned within the chamber have intermeshing lobes and valleys for turning in the chamber as fluid flows from the inlet through the chamber to the outlet. At least one of the rotors has a radial recess for receiving a magnet. A shaft mount is connected to the wall plate. A response shaft is rotationally mounted in the shaft mount, and an indicator rotates with the shaft. A first magnetic coupling is mounted in the rotor recess. A second magnetic coupling is mounted on the shaft within the rotor hub and within the first magnetic coupling for rotating the second magnetic coupling, the shaft, and the indicator in response to rotation of the rotors. First paired coin-shaped magnets are aligned on magnetic axes extending diametrically through the rotor axis. Second grouped coin-shaped magnets are aligned on the single magnetic axis within the rotor hub.

Abstract: A fluid volumetric flowmeter has a casing forming a chamber, a fluid inlet, and a fluid outlet communicating with the chamber. Two rotors positioned within the chamber have intermeshing lobes and valleys for turning in the chamber as fluid flows from the inlet through the chamber to the outlet. At least one of the rotors has a facial recess for receiving a magnet. A shaft mount is connected to a wall of the casing. A response shaft is rotationally mounted in the shaft mount. An indicator connected to the shaft rotates with the shaft. A first magnetic coupling is mounted in the rotor recess of the rotor. A second magnetic coupling is mounted on the shaft near the first magnetic coupling for rotating the second magnetic coupling, the shaft, and the indicator in response to rotation of the rotors.