Patents by Inventor Jean R. Dupain

Jean R. Dupain has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4849175
    Abstract: A method and apparatus for automatically measuring the grain fineness, the gypsum content and the limestone content of a cement sample.A first fraction of the sample is loaded by a vibrating hopper into a crucible resting on an automatic scale. This crucible is handled sequentially by tongs on two revolving arms carried on slidable vertical shafts. The circular paths of the arms intersect at a point just above the scale. Motions of the arms and of the tongs are controlled by a programming unit. The weighed sample is poured into a sieve and the weight of oversize grains is automatically related to the sample weight.Gypsum is measured by heating a second fraction of the sample at 1000.degree. C. plus in an oxygen stream, Fe powder being added from a fixed hopper. The crucible is raised into an induction furnace. Released SO.sub.2 is bubbled in a titration cell to which potassium iodate is gradually added by a burette giving an automatic read-out of the SO.sub.3 (gypsum) titration.
    Type: Grant
    Filed: January 4, 1988
    Date of Patent: July 18, 1989
    Assignee: Societe Des Ciments Francais
    Inventors: Jean R. Dupain, Christian P. Vernet