Low cost, single stroke, electromagnetic pre-charge pump for controlled brake systems

The subject invention relates generally to an improved precharge pump for use with a controlled brake system. A fluid pump assembly for pumping hydraulic fluid through a controlled brake system includes a housing defining a pumping chamber. The chamber communicates with a hydraulic fluid circuit that operates the controlled brake system. A piston plunger is disposed within the chamber with a shaft affixed to the plunger. An electric coil is affixed to a casing having the shaft inserted therethrough. The coil is coaxially aligned with the shaft. The coil generates a magnetic field through an armature affixed to a distal end of the shaft disposed outside the chamber when receiving electrical current. The magnetic field draws the armature towards the casing for pumping hydraulic fluid from the chamber.