Apparatus for determining the density of pulveralent materials in a reservoir by means of a radioactive source and detector

Claim 2

Apparatus for checking the level or the density of a mass of pulverulent mineral residues in a normally closed hopper, said hopper including downwardly convergent sidewalls defining a reservoir for such mass and having an outlet at the bottom thereof for delivering material therefrom by gravity flow, comprising two tubular members protruding through said sidewalls into said reservoir from opposite sides thereof at a level above said outlet, said tubular members being aligned axially one with the other and having respective inner ends closed off by end walls thereof and spaced apart inside said reservoir, means associated with the outer end of one of said tubular members for directing electromagnetic radiation axially along the spaces inside said members so as to pass the radiation through said end walls and any mass of material lying in the space between them, said end walls being composed of a material pervious to said radiation, and means associated with the outer end of the other of said tubular members for detecting the amount of said radiation transmitted through said end walls and any such mass of material.

Claim 3

Apparatus according to claim 1, said first-recited means being a source of gamma radiation and each of said end walls being a thin sheet of stainless steel.

Claim 4

Apparatus according to claim 1, said first-recited means being a source of gamma radiation and said second recited means being a Geiger counter.

Claim 5

Apparatus according to claim 1, and means for conducting forced streams of gas about said tubular members and directing said streams over the faces of said end walls inside said reservoir.

Claim 6

Apparatus according to claim 1, the face of each of said end walls being sloped from the top thereof downwardly and outwardly in the direction away from the path of material falling between said end walls toward said outlet.

Claim 7

Apparatus according to claim 1, and means mounted on each of said tubular members for vibrating said members so as to prevent material in said reservoir from accumulating on said end walls.

Claim 8

Apparatus for checking the level or the density of a mass of pulverulent mineral residues in a normally closed hopper, said hopper including downwardly convergent sidewalls defining a reservoir for such mass and having an outlet at the bottom thereof for delivering material therefrom by gravity flow, comprising two tubular members protruding through said sidewalls into said reservoir from opposite sides thereof at a level above said outlet, said tubular members being aligned axially one with the other and having respective inner ends closed off by end walls thereof and spaced apart inside said reservoir, means associated with the outer end of one of said tubular members for directing gamma radiation axially along the spaces inside said members so as to pass the Radiation through said end walls and any mass of material lying in the space between them, said end walls being composed of a material pervious to said radiation, a Geiger counter associated with the outer end of the other of said tubular members for detecting the amount of said radiation transmitted through said end walls and any such mass of material, the inner face of each of said end walls being sloped from the top thereof downwardly and outwardly in the direction away from the path of material falling between said end walls toward said outlet, and means for conducting forced streams of gas about said tubular members and directing said streams over the inner faces of said end walls inside said reservoir to prevent the formation of deposits on said faces.

Claim 9

Apparatus for checking the level or the density of a mass of pulverulent mineral residues in a normally closed hopper, said hopper including downwardly convergent sidewalls defining a reservoir for such mass and having an outlet at the bottom thereof for delivering material therefrom by gravity flow, comprising two tubular members protruding through said sidewalls into said reservoir from opposite sides thereof at a level above said outlet, said tubular members being aligned axially one with the other and having respective inner ends closed off by end walls thereof and spaced apart inside said reservoir, means associated with the outer end of one of said tubular members for directing gamma radiation axially along the spaces inside said members so as to pass the Radiation through said end walls and any mass of material lying in the space between them, said end walls being composed of a material pervious to said radiation, a Geiger counter associated with the outer end of the other of said tubular members for detecting the amount of said radiation transmitted through said end walls and any such mass of material, the inner face of each of said end walls being sloped from the top thereof downwardly and outwardly in the direction away from the path of material falling between said end walls toward said outlet, and means for conducting forced streams of gas about said tubular members and directing said streams over the inner faces of said end walls inside said reservoir to prevent the formation of deposits on said faces.