Electromagnetic Water Pump Clutch: Working Principle, Design Strategies and Applications for Heavy-Duty Vehicles

Current development activities on modern heavy-duty diesel engines are aimed primarily on reducing emissions and improving fuel consumption. This paper describes how the water pump, traditionally driven from the crankshaft through a mechanical link, can be enhanced to satisfy increased demands for coolant flow for new engine strategies and also save power by eliminating unnecessary operation. An electromagnetic 2-speed clutch, incorporated into the overall envelope of the water pump allows the engine control system to select the best pump speed for any given operational condition. The presented underlying principles, technical solutions and prototype experiences demonstrate the utility of this new component.