Patents by Inventor Stephen L. Markle

Stephen L. Markle 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: 5368390
    Abstract: A mixer system for aggressive (toxic, hazardous, corrosive, etc.) materials which are mixed (agitated, suspended, circulated, etc.) in a tank with an impeller connected to a drive shaft has the impeller and its shaft mounted in an assembly which extends through an opening into the tank and closes that opening. The assembly has a cylindrical hub with a passageway through which the shaft extends out of an open end of the hub. Bearings which are made of materials which are resistant to the aggressive material in the tank are mounted in the hub and journal and support the shaft. There are no dynamic seals which close the confinement region so that the aggressive materials can be present therein.
    Type: Grant
    Filed: March 1, 1993
    Date of Patent: November 29, 1994
    Assignee: General Signal Corporation
    Inventors: Jeffrey S. Gambrill, William F. Hutchings, Stephen L. Markle, Marlin Schutte, John M. Palmer
  • Patent number: 4753534
    Abstract: Mixing apparatus having a sealed impeller shaft provided by a seal unit which supports the shaft and to which a motor drive unit may be detachably connected. When the motor drive unit is disconnected, the mixing apparatus may be sterilized, along or together with the vessel containing the material to be mixed and to which the seal unit is attached. The seal unit has a seal assembly with a movable part engageable by a drive shaft in the drive unit when the drive unit is mounted on the seal unit. The movable seal part is biased to move to a position against a mounting plate on which the drive unit is mounted when the drive mounted is removed so as to provide a static seal. When the drive unit is attached to the seal unit, the driven shaft engages the moveable seal unit part and moves it to another position away from the mounting plate, where the seal assembly may freely rotate with the impeller shaft and maintain a dynamic seal.
    Type: Grant
    Filed: May 28, 1987
    Date of Patent: June 28, 1988
    Assignee: General Signal Corp.
    Inventor: Stephen L. Markle
  • Patent number: 4418251
    Abstract: The electrical collector unit (41) and the overhead conductor entrance (26) are designed so that four collectors (63, 64, 66, 67) can properly enter the conductor slots (18, 19, 21, 22) without manual assistance and with the vehicle, not shown, carrying the collection unit (41) traveling at near a walking speed. Two collector subassemblies (42, 43) are mounted on the vehicle, not shown, each of which carries two collectors and includes spring biased parallel links (73, 74, 76, 77) between a pair of pivot posts (71, 86), a guide roller (61) engageable with side walls (28, 29, 36, 67) of the entrance chute (26) and equalizer beams (134, 136) supporting the collectors (63, 64 or 66, 67).
    Type: Grant
    Filed: December 21, 1981
    Date of Patent: November 29, 1983
    Assignee: Allis-Chalmers Corporation
    Inventors: Peter W. Hartman, Keith E. Hanford, Stephen L. Markle, Elmer C. Hartman
  • Patent number: D322322
    Type: Grant
    Filed: September 20, 1988
    Date of Patent: December 10, 1991
    Assignee: General Signal Corporation
    Inventors: Stephen L. Markle, William F. Hutchings, Daniel J. Bentley
  • Patent number: D323663
    Type: Grant
    Filed: May 25, 1989
    Date of Patent: February 4, 1992
    Assignee: General Signal Corporation
    Inventors: Stephen L. Markle, David J. Engel, William F. Hutchings