	US 7,387,095 B2
	Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves
Guy Robert Babbitt, Colorado Springs, Colo. (US); Miguel Angelo Raimao, Manitou Springs, Colo. (US); Charles Conrad Klose, Plainfield, Ill. (US); Jeffrey Allen Rogers, Woodland Park, Colo. (US); and Oded Eddie Sturman, Woodland Park, Colo. (US)
Assigned to Sturman Industries, Inc., Woodland Park, Colo. (US)
Filed on Apr. 08, 2005, as Appl. No. 11/102,192.
Claims priority of provisional application 60/560561, filed on Apr. 08, 2004.
Prior Publication US 2005/0263116 A1, Dec. 01, 2005
Int. Cl. F01L 9/02 (2006.01)

U.S. Cl. 123—90.12 [123/90.15; 123/90.24; 251/285; 251/284]

36 Claims

1. An engine valve actuation system comprising:

in a camless engine;

a first actuator configured to actuate an engine valve between an engine valve closed position and engine valve open positions;

a second actuator moveable between first and second positions, when in the first position the second actuator being configured to define a stop limiting the engine valve opening to a first lift, and when in the second position the second actuator being configured to define a stop limiting the engine valve opening to a second lift different from the first lift, the first and second actuators being hydraulic actuators; and,

said camless engine having a unidirectional dashpot operative in a single direction only, and limiting engine valve velocity as the engine valve approaches either of the first and second lifts.