INTERNAL GEARING HYDRAULIC MOTOR AND ITS SEALING UNIT Russian patent published in 2001 - IPC

FIELD: mechanical engineering; hydraulic drives of machine working members. SUBSTANCE: proposed hydraulic motor has housing with internal teeth, rotor with two gear rims eccentrically installed in housing, inner rim being brought into engagement with shaft-gear teeth forming variable-capacity working chambers in zone of engagement, and distributors provided with channels along which indicated chambers are placed in communication with working liquid inlet and outlet spaces. Hydraulic motor is provided with hollow sleeve. Shaft-gear is made hollow, with concentric bores accommodating sleeve which is installed stationary relative to shaft- gear to form outer and inner concentric working liquid inlet and outlet spaces. Inner space consists of two separated ring chambers placed in communication with each other. Distributors are arranged at two sides relative to rotor. Working liquid inlet and outlet inner space communicates with distributor channels through holes made in side wall of hollow sleeve. One end of sleeve is fixed in seals in hydraulic motor cover to place inner space of sleeve in communication with one of channels along which hydraulic motor communicates with reversible hydraulic distributor. One of ring chambers in gear shaft-gear communicates with other channel along which hydraulic motor communicates with indicated hydraulic distributor. To prevent leakages when hydraulic motor operates at high pressures, sealing unit has flexible deformable ring-shaped element installed in ring groove of housing or cover of hydraulic motor, and bushing made of fluoroplastic on outer surface of which cavities of made. This bushing encloses shaft or tubular element, being arranged between tubular element and flexibly deformable ring-shaped element. Owing to the fact that, in hydraulic motor with shaft rotating in fixed housing, ring rotor plays the part of spool, number of movable members is reduced. EFFECT: reduced labour input at manufacturing, increased reliability. 3 cl, 4 dwg