EP 1067293 A2 20010110 - Electro-hydraulic actuator and method for controlling actuator position
Title (en)
Electro-hydraulic actuator and method for controlling actuator position
Title (de)
Elektrohydraulisches Stellglied und Regelungsverfahren eines Stellglieds
Title (fr)
Vérin de positionnement électrohydraulique, et procédé pour le réglage de la position du vérin
Publication
Application
Priority
US 14324399 P 19990709
Abstract (en)
A fluid actuator (10) achieves precise placement without external feedback by employing a spool (44) slidable within a piston (20). The relative positions of the piston (20) and the spool (44) determine whether pressurized fluid is applied to extend the piston, to retract the piston, or to maintain the position of the piston. The spool (44) is positioned by balancing a spring (46) force on one end with a variable pressure force on the other end, the variable pressure fluid for providing the variable pressure force being supplied by a pulse width modulation valve (28) which is mounted in the actuator (10). The pressure of the fluid supplied by the modulation valve (28) is a function of an input such as an electrical signal received by the valve. The position of the piston (20) is determined by the position of the spool (44). In an exemplary embodiment, an actuator positions the vanes of a turbocharger of a motor vehicle engine. The pressurized fluid used is the crankcase oil of the engine. <IMAGE>
IPC 1-7
IPC 8 full level
F15B 9/12 (2006.01); F15B 15/20 (2006.01)
CPC (source: EP)
F15B 9/12 (2013.01); F15B 15/202 (2013.01)
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
DOCDB simple family (application)
EP 00305750 A 20000707