Patent ID: 8464592

Claim:
An apparatus for measuring the compressed volume of a particulate material comprising a chamber for containing a particulate material which will be evaluated; removable, fixed means at one end of said chamber to enclose said chamber and for containing said particulate material within said chamber; compression means at the other end of said chamber which further encloses and contains said particulate material within said chamber and which provides a linear force on said particulate material so that one end of said particulate material is linearly movable and said compression means will compress the particulate material in said chamber; said compression means comprising a movable piston; means for measuring the distance between said movable piston and said fixed means so to measure the thickness of said compressed particulate material; and measuring means on the moveable piston of said chamber for measuring the applied force of said piston to said particulate material when said piston is compressing said particulate material; further characterized in that the apparatus includes decompression means to move said moveable piston away from a particulate material placed inside said chamber to decompress the particulate material in said chamber; and the apparatus includes a means to control the movement of the moveable piston so that the velocity and force can be varied and controlled to be stable during compression up to a pre-set maximum force and during decompression down to full expansion and its movement during compression or decompression is smooth and continuous.