Patents by Inventor Stephen J. Lieland

Stephen J. Lieland 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).

  • Control system for hydraulic presses
    Patent number: 4721028
    Abstract: A control system for controlling the movement of the slide of a hydraulic press of the type having a main cylinder containing a piston mounting the slide. The control system comprises an electronic processor, a pressure transducer to measure the pressure of hydraulic fluid applied to the piston to move the slide downwardly, a position encoder coupled to the slide to determine the vertical position of the slide, and a hydraulic circuit to supply hydraulic fluid under pressure to the cylinder to move the piston and slide upwardly and downwardly. The hydraulic circuit comprises a plurality of cartridge valves having controls actuable by outputs from the processor.
    Type: Grant
    Filed: April 2, 1985
    Date of Patent: January 26, 1988
    Assignee: Cincinnati Incorporated
    Inventors: Delbert E. Lucas, Stephen J. Lieland
  • Control system for hydraulic presses
    Patent number: 4524582
    Abstract: A control system for controlling the movement of the slide of a hydraulic press of the type having a main cylinder containing a piston mounting the slide. The control system comprises an electronic processor, a pressure transducer to measure the pressure of hydraulic fluid applied to the piston to move the slide downwardly, a position encoder coupled to the slide to determine the vertical position of the slide, and a hydraulic circuit to supply hydraulic fluid under pressure to the cylinder to move the piston and slide upwardly and downwardly. The hydraulic circuit comprises a plurality of cartridge valves having controls actuable by outputs from the processor.
    Type: Grant
    Filed: March 31, 1983
    Date of Patent: June 25, 1985
    Assignee: Cincinnati Incorporated
    Inventors: Delbert E. Lucas, Stephen J. Lieland