F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
F16D25/00—Fluid-actuated clutches
F16D25/06—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch
F16D25/062—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces
F16D25/063—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces with clutch members exclusively moving axially
F16D25/064—Fluid-actuated clutches in which the fluid actuates a piston incorporated in, i.e. rotating with the clutch the clutch having friction surfaces with clutch members exclusively moving axially the friction surface being grooved