Abstract: To reduce the peak torque required by an electric motor-driven high-pressure piston-type fuel pump, a drive assembly between the motor and pump includes an energy accumulator configured to accumulate energy during a low force portion of the pump cycle and return that energy to the pumping plunger during a high force portion of the pump cycle. This arrangement reduces the peak torque required from the motor and allows a smaller, less expensive and less energy intensive electric motor to drive the pump.

Abstract: A compact EGR valve uses a BLDC motor to drive a valve member between a closed position blocking flow of exhaust gases and a range of open positions where exhaust gasses flow through the valve. A drive mechanism includes a nut in a fixed position and a screw arranged to rotate within the nut so that rotation of the screw causes the screw to move axially relative to the nut. The screw is coupled to a valve member and the valve member moves axially and rotationally with the screw. The screw slides along the length of a motor shaft as the screw moves axially relative to the nut and motor. Rotation of the valve member within the valve chamber during axial movement aids in removal of deposits that may accumulate within the valve housing.

Abstract: An actuator is driven by a brushless motor having a rotor with axially extended magnets, permitting axial movement of the rotor while maintaining overlap between the magnets and a stator secured in a fixed position. The rotor is engaged with a fixed structure by a connection such as a ramp or thread that translates rotation into axial movement of the rotor along a rotational axis of the actuator. A valve member coupled to the rotor moves axially between a closed position and a range of positions that regulate fluid flow through a valve. A motor control circuit applies power to the stator coils to rotate the rotor and coupled valve member to a desired axial position and maintain the rotor and valve member at the selected position. The rotor and valve member may be biased toward a rotational position corresponding to a closed position of the valve member.

Abstract: An actuator is driven by a brushless motor having a rotor with axially extended magnets, permitting axial movement of the rotor while maintaining overlap between the magnets and a stator secured in a fixed position. The rotor is engaged with a fixed structure by a connection such as a ramp or thread that translates rotation into axial movement of the rotor along a rotational axis of the actuator. A valve member coupled to the rotor moves axially between a closed position and a range of positions that regulate fluid flow through a valve. A motor control circuit applies power to the stator coils to rotate the rotor and coupled valve member to a desired axial position and maintain the rotor and valve member at the selected position. The rotor and valve member may be biased toward a rotational position corresponding to a closed position of the valve member.