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A small, low-cost damper is developed to attenuate fuel rail pulsation caused by hydraulic hammer. Rail hammer is of special concern when using returnless fuel systems, affecting emissions, drive-ability, and creating noise. The new development, utilizing a springbiased diaphragm damper, replaces the fuel line connector serving the rail. High performance damping is achieved through a unique design permitting significant mass, volume, and cost savings. The low mass and the packaging advantage of the new damper permit additional system cost savings by eliminating the conventional rail interface components and labor. This function integrated into the fuel line connector of the rail permits pulsation damping to be added to an existing system without rail modification and without additional fuel connections, thereby maintaining the system's integrity with respect to hydrocarbon permeation and leakage.

Returnless fuel delivery systems are being developed to assist the vehicle OEM to meet lower emissions requirements for evaporative hydrocarbons from the vehicle. Because the fuel return line contributes to much of this vapor formation, its elimination is desirable. Existing returnless delivery techniques are considered including mechanical and electronic means for pressure regulation. A unique returnless system, called Demand Delivery System (DDS) incorporates desirable attributes of the existing techniques and provides additional functions of a rail mounted micro-size demand regulator. This DDS system eliminates the return line and its cost, providing significant reduction of vapor generation in the fuel tank. The Demand regulator provides rail pulsation damping, the ability to manifold vacuum reference, an accumulator function during hot soak, accommodation of dynamic line and filtration losses, and superior transient response to dynamic engine demands.

A two-speed DC motor utilizing a dual armature winding has been developed as an improved solution to fan speed control with respect to cost, reliability, power conversion efficiency, electro-magnetic compatibility, speed flexibility, and packaging concerns. This development provides a simple means to select fan speeds optimally satisfying the air conditioning and engine cooling systems demand for heat rejection with lower noise and power consumption. This two-speed motor can also be employed in a two-fan system to output a variable voltage to speed control a second conventional fan motor. In this manner, the second motor acquires these advantages of the dual-wind motor. In addition, system advantages are gained by commonizing the RFI suppression for each motor and, in simplifying the vehicular wire harness connection to the two-fan system.