Patent attributes
An automatic transmission having at least one hydraulic valve with flow force compensation. The hydraulic valve includes a valve body having a valve bore and at least one inlet and at least one outlet adapted to provide fluid communication with a source of pressurized hydraulic fluid and a return to the source of pressure. A valve member is slidingly disposed within the valve body that includes at least one valve element having an outer diameter and a metering face. The metering face is adapted to control the flow of pressurized hydraulic fluid between the inlet and the outlet of the valve body. The metering face includes a flow force compensating annular void disposed adjacent to the outer diameter that is defined by a lead angle α measured between the outer surface and a line intersecting the outer surface and tangential to the annular void.
