Patent ID: 8234956

Claim:
A piston-actuated synchronizer system comprising: a cylindrical collar keyed to a cylindrical piston, the cylindrical collar and the cylindrical piston sharing a first common rotational axis; a cylindrical driven gear and a spline associated with and fixed to the cylindrical driven gear, the cylindrical driven gear and spline sharing a second common rotational axis, the second common rotational axis being coincident with the first common rotational axis; the cylindrical piston being axially movable along the second common rotational axis and having a flange thereon for engaging a step on the cylindrical collar to translate the cylindrical collar axially toward the spline, the cylindrical piston further including an annular keyway formed on an outer surface thereof, the cylindrical piston being supported by a hub with a cylindrical cavity formed between the cylindrical piston and the hub, the cylindrical cavity having at least one fluid inlet in fluid communication therewith; a solenoid valve for regulating a flow of fluid from the at least one fluid inlet into the cylindrical cavity to force the cylindrical piston and the associated cylindrical collar axially toward the spline to engage the cylindrical collar therewith, and a spring for biasing the cylindrical driven collar away from the spline; a housing having a displacement sensor thereon, the displacement sensor being adapted to detect an axial position of the driven collar and to produce a signal indicative of the axial position of the driven collar; and a sensor target positioned between the cylindrical piston and the housing and having a portion positioned within the annular keyway of the cylindrical piston.