F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
F15B11/12—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor providing distinct intermediate positions; with step-by-step action