Patents Assigned to Piper-Mechadyne Limited
  • Internal combustion engines
    Patent number: 4995358
    Abstract: A dual duct porting system comprises a pair of juxtaposed bent, side entry supply ducts (14, 15) merging into a single supply passage (16) encircling a valve stem (13). Each supply duct (14, 15) has eddy creating means (20) provided at a radially inner region of the duct bend and an outwardly bulging portion (21) at a radially outer region of the duct bend to provide a flow in the merged passage (16) which is more evenly spread around the valve head to be shed therefrom as evenly distributed toroidal vortices.
    Type: Grant
    Filed: April 11, 1990
    Date of Patent: February 26, 1991
    Assignee: Piper-Mechadyne Limited
    Inventors: Robert J. Gayler, Timothy M. Lancefield