Cylindrical tooth set having a concave socket and a cylindrical tooth engaging each other on the transverse line of eccentricity

A cylindrical tooth set comprising an axleless rotor tooth member having a longitudinal rotor axis, a stator tooth member surrounding said rotor tooth member and having a longitudinal stator axis substantially parallel to said rotor axis, said rotor axis and said stator axis being mutually spaced apart from each other and defining a transverse line of eccentricity passing therethrough, said axleless rotary tooth member being internally unsupportable, the longitudinal axis of one of said tooth members being disposed to move in an orbital cycle about the longitudinal axis of the other of said tooth members, said rotor tooth member having an outer face, said outer face having said rotor axis as a center, said stator tooth member having an inner face, said inner face having said stator axis as a center, said rotor tooth member having mounted therein a plurality of rotor cylindrical teeth projecting outwardly from said outer face thereof, all of said rotor teeth having substantially the same rotor tooth diameter and being spaced apart one from the other in a circumferential direction, said stator tooth member having mounted therein a plurality of stator cylindrical teeth projecting inwardly from said inner face thereof, said rotor teeth being one less in number than the number of said stator teeth, all of said stator teeth having substantially the same stator tooth diameter and being spaced apart one from the other in a circumferential direction, said rotor and stator teeth being disposed to intermesh with each other and form expandable and contractable fluid chambers therebetween, said rotor tooth member defining a plurality of rotor body portions between the rotor teeth thereof, all of said rotor body portions having substantially the same circumferential width and respectively being provided with a longitudinal concave socket, one of said concave sockets being referred to as a middle concave socket and one of said plurality of cylindrical stator teeth being referred to as a middle stator tooth, said middle concave socket and said middle stator tooth being disposed to provide a concave-to-convex contact relationship therebetween, said middle stator tooth in said contact relationship defining an individual stator tooth axis, said concave socket in said relationship defining an individual socket axis, said transverse line of eccentricity passing through said individual stator tooth axis and said individual socket axis, said concave sockets respectively defining a socket diameter greater than the diameter of said stator teeth.