Patent ID: 9702863
Date: 2017-07-11
CPC Classifications: B28C,G01N

Claim:
1. A method of generating a signal indicative of buoyancy of a buoy immersed in fresh concrete contained in a ready mix drum rotatable about a central axis, the central axis being at least partially horizontally-oriented, said buoy being mounted on an inner surface of said drum and moved along a circular path when the drum is rotated, said method comprising: rotating the drum about the central axis, to move the buoy inside said fresh concrete across a vertical minimum position along the circular path, and measuring a first force exerted on said buoy as said buoy is moved across the vertical minimum position, said first force being representative of yield stress; rotating the drum about the central axis, to move the buoy inside said fresh concrete across a maximum lateral position along the circular path, and measuring a second force exerted on said buoy as said buoy is moved across the maximum lateral position, said second force being representative of combined yield stress and buoyancy; subtracting the measured first force across the vertical minimum position from the measured second force across the maximum lateral position; and generating a signal indicative of said buoyancy based at least on said subtraction.