Patents by Inventor John L. Maliszewski

John L. Maliszewski 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: 6158973
    Abstract: A multi-stage manual hydraulic pump comprising a plurality of cylinders in tandem. A block holds each cylinder assembly. One or more cylinders are the high volume stage, one or more cylinders are the medium volume stage and the final cylinders are the low volume, high pressure stage. The pump utilizes check valves built into flow tubes that control the direction of fluid. A variable hydraulic piston and cylinder assembly in each high volume block and each medium volume block automatically turns off the vacuum and flow of fluid to each cylinder at a designated pressure. At the point of highest pressure only the smallest cylinder or cylinders are pumping fluid, where the effort expended is significantly reduced.
    Type: Grant
    Filed: March 27, 2000
    Date of Patent: December 12, 2000
    Assignee: Trench Plate Rental Co., Inc.
    Inventor: John L. Maliszewski
  • Patent number: 6079956
    Abstract: A multi-stage manual hydraulic pump comprising a plurality of cylinders in tandem. A block holds each cylinder assembly. One or more cylinders are the high volume stage, one or more cylinders are the medium volume stage and the final cylinders are the low volume, high pressure stage. The pump utilizes check valves built into flow tubes that control the direction of fluid. A spring and piston in each high volume block automatically turns off the vacuum and flow of fluid to each cylinder at a designated pressure. At the point of highest pressure only the smallest cylinder or cylinders are pumping fluid, where the effort expended is significantly reduced.
    Type: Grant
    Filed: March 26, 1998
    Date of Patent: June 27, 2000
    Assignee: Trench Plate Rental Co., Inc.
    Inventor: John L. Maliszewski