HYDRAULIC DRIVE Russian patent published in 1998 - IPC

FIELD: automatic control of working members and processes under extreme conditions. SUBSTANCE: hydraulic drive has digital-to-analog converter with piston circuit and rod engaging with spool type distributing device. Digital-to-analog converter is coupled by hydraulic main lines with slave motor setting into operation output shaft of drive. Feedback cam with involute generatrix is secured on drive output shaft, involute circumference being coaxial with drive output shaft. Roller is installed on rod of digital-to-analog converter. Axis of roller is parallel to output shaft of drive and is arranged in plane passing through axis of output rod of digital-to-analog converter and roller-to-cam contact line. Axis of output rod of digital-to-analog converter is arranged tangentially to circumference of cam involute. Making of involute circumference coaxially with drive output shaft, arrangement of roller axis in plane passing through axis of output rod of digital-to-analog converter and roller-to-cam contact line and arrangement of axis of output rod of digital-to-analog converter tangentially to feedback cam involute circumference make it possible to eliminate out-of-center clamping of output shaft of digital-to-analog converter which decreases friction of output rod of converter in housing owing to decreasing radial component of effort during its engagement with feedback cam. EFFECT: improved reliability of operation. 2 dwg