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Department of Engineering, ICT and Technologies for Energy and Transport Patent Title Electrohydraulic valve with linear and rotĂƟŽnal actuĂƟon. Ref. CNR 10227 Assignee(s): CNR CNR InƐƟƚute: IMAMOTER Main Inventor: Massimiliano Ruggeri Countries: IT Priority date: 02/08/2012 Abstract The inveŶƟŽn refers to an electro-valve that consists in two mobile elements: the Įst one is a cylinder moving around its axis and the second one is a spool with linear travel. The metering area of the valve is therefore the combinĂƟon of two independent movements. The object of the inveŶƟŽn features a metering accuracy higher than tradŝƟŽnal implemeŶƚĂƟŽŶƐ - typically in the range of a square product. Since the ĂĐƚƵĂƟŽn is intrinsically redundant, the valve has a high safety and reliability index and can be used to implement various metering logics, as for instance hydraulic AND and OR. Background WƌŽƉŽƌƟŽnal valves are used since a long Ɵŵe in various applŝĐĂƟŽŶƐ in mobile machinery and industrial hydraulics. Today’s technology is based on linear actuaƟŽn only seldom featuring ŵƵůƟƉůĞ elements. WƌŽƉŽƌƟŽnal valves may be used in safety ĐƌŝƟĐĂů applŝĐĂƟon only if deployed in redundant architectures and their metering edges can be ŽƉƟŵŝnjĞd on one ŽƉĞƌĂƟŶŐ ƉƌŽĮůĞ only. The ŝŶǀĞŶƟŽn overcomes all of these limŝƚĂƟŽŶƐ͘ Technology The valve with linear and roƚĂƟonal actuĂƟons is a novel applicaƟon of rotary actuators; it introduces an adĚŝƟonal degree of freedom in the handling of the metering area. Two coaxial stages of the metering elements (cylinder and spool) feature an extremely compact ŝŵƉůĞŵĞŶƚĂƟŽn. Advantages and ApplicaƟons The valve features several advantages with respect to state of the art technology: the system is «Fail OpĞƌĂƟŽŶĂů» and therefore can conƟŶƵĞ ĨƵŶĐƟŽŶŝŶg even in case of a single failure in ĂĐƚƵĂƟŽn stages. It can be applied and is suited for systems like steer, ŇLJ͕ brake-by-wire (generally x-by-wire). The valve has a ďĞƩĞƌ accuracy and an increased Ňexibility with respect to exisƟŶŐ technology, adapƟŶŐ area gains to applicaƟons and duty cycles of diīerent appliĐĂƟons. Development stage The valve is ready to be engineered and prototyped and it has been ĐŚĂƌĂĐƚĞƌŝnjed in a virtual environment; iƟ s now ready for prototype development. 19