Patent ID: 6743005
Filing Date: 2004-06-01
Classification: F04C

Abstract:
A hydraulic gerotor motor comprising:(a) a housing provided with a cylindrical gerotor bore; (b) an outer gerotor gear mounted within said gerotor bore, said outer gerotor gear having a smooth, cylindrical outer perimeter facing said gerotor bore to define a region of radial clearance therebetween; and an inner perimeter equipped with inwardly extending teeth; (c) an inner gerotor gear mounted within said outer gerotor gear, said inner gerotor gear having outwardly extending teeth engaging said inwardly extending teeth of said outer gerotor gear; (d) an inlet port situated for receiving a flow of hydraulic fluid and delivering said hydraulic fluid to a region of engagement between said inwardly extending teeth and said outwardly extending teeth; (e) an outlet port situated for discharging used hydraulic fluid from said device; and (f) a pressure balancing passage extending between said region of radial clearance and said inlet port; wherein said pressure balancing passage causes creation of an inlet pressure region at said region of radial clearance, said inlet pressure region being centered within 20 degrees of a radial line perpendicular to an offset line joining said inner gerotor center and said outer gerotor center and having an arc length greater than 30 degrees.