A Novel, Fully Flexible, Electro-Mechanical Engine Valve Actuation System

Automotive Electrification: The Nonhybrid Story

“…Such a system has the advantage of retaining the cam system that provided the smooth and reliable seating known of mechanical systems [65].…”

A Fully Flexible Valve Actuation System for Internal Combustion Engines

“…A fully flexible camless valve mechanism [1][2] [3] allows controlling the engine load without a separate throttle and thereby avoids the associated energy loss, which will be discussed in next section. It is also known that in a conventional engine the control of valve overlap, during which both the intake and exhaust valves are open, can affect the emissions, full load and idle performance.…”

An Electromechanical Valve Drive Incorporating a Nonlinear Mechanical Transformer

“…In industrial or commercial engines, where noise is not a serious problem, rarnp velocity may be as high at 0.0015 in/deg [6]. Another reference gives seating velocity requirement of less than 3 cmls at an engine speed of 600 rpm and 30 cmls at 6000 rpm [8]. I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I ___~L~__ J J 1 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I - Fig.…”

“…Another interesting design is OM's rotary motor type EMVD [8], which uses inertia instead of springs as the regenerative device. The design needs power to provide VVA functions in addition to power to compensate for external forces and losses, and the flexibility of this design is limited in practice.…”

“…The design needs power to provide VVA functions in addition to power to compensate for external forces and losses, and the flexibility of this design is limited in practice. For example, at high engine speeds, it is very hard to change valve profiles from base profiles for duration and/or lift control due to power limitations [8].…”