Patents by Inventor Lennart Backstrom

Lennart Backstrom 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: 4900454
    Abstract: Method and apparatus for pressure filtering in a pressure filter (1) comprising a frame carrying press plates (3-6), which can be brought together and apart, said press plates between themselves forming pressure chambers (8). In each pressure chamber there are two filter cloths (9) forming a filter element, said filter cloths being connected to each other in one piece and hanging down from a suspension rod (58) resting on guide rails (86). During operation a suspension of solid particles in a liquid is introduced between the filter cloths (9) in the pressure chambers (8). The liquid is pressed through the filter cloths (9) under the influence of membranes (7) loaded by a pressurized medium and by blowing through a gas and is removed through drain channels (10, 12, 14). The filter cakes (40) remaining between the filter cloths (9) are discharged after bringing apart the press plates (3-6) by vibrating (98) of the filter cloths (9).
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: February 13, 1990
    Assignee: Sala International AB
    Inventors: Hans-Goran Hedlund, Lennart Backstrom