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Traditional in-tank gasoline and diesel fuel pumps require high power, 120 W or more, in fuel systems that have high flow requirements, high pressure requirements, or both. One method to reduce power consumption is to improve efficiency by using a brushless motor rather than the traditional brush style motor. The brushless motor technology also eliminates the brush to commutator interface which improves the pump's robustness to fuel and reduces flow variation. Additional benefits are provided by the controller which provides motor commutation since it enables closed loop pump speed control, pump diagnostics, and the opportunity for additional sensor interfaces to improve the fuel delivery system architecture. This paper describes the brushless motor technology, design optimization strategy for fuel pump applications, selected design, and resulting torque and efficiency performance improvements.

Ever since the implementation of diagnostics and electronic control systems on automatic transmissions, various forms of transmission gear selection feedback has been used. The traditional mechanization uses a feedback switch with mechanical contacts that indicate the selected gear discretely or through a grey code output. Switch reliability above the industry standard was made possible through the use of non-contact technology. Multi-Hall mechanizations have been used by others in recent years however this type of product has been simplified by using a single linear Hall device; reducing component count and the number of connector interfaces. Furthermore, a reduction in the number of electrical connections led to improved system reliability and cost. Optimization of this package was made possible through the use of a multi-tool, multi-objective, single field focus using advanced design optimization software, robust engineering techniques and Shainin® tools.

Modern automatic transmissions use various methods to estimate fluid line pressures in order to improve shift quality and reduce energy losses. These estimations lead to improvements in fuel economy, customer satisfaction and reduced exhaust emissions. The further addition of pressure feedback switches improves operational knowledge by verifying when clutches have received their commanded pressures. Product reliability above the industry standard for transmission pressure switches was developed through the use of multiple FEA platforms combined with advanced design optimization software, robust optimization and Shainin® tools. In this optimized design, ferromagnetic non-contact pressure switches operate by translating fluid pressure into piston motion, isolated by a sealed proprietary diaphragm.