Patent ID: 8915642
Filing Date: 2014-12-23
Classification: B29B,B29C,Y10T

Abstract:
1. A method of generating planar, tightly intermeshing, self-cleaning, co-rotating screw profiles with a selectable centre distance of axes a between the rotational axes of a generating and a generated screw profile, wherein the generating screw profile is formed from n circular arcs and the generated screw profile is formed from n′ circular arcs, wherein the generating screw profile and the generated screw profile are located in a same plane, wherein an axis of rotation of the generating screw profile and an axis of rotation of the generated screw profile are, in each case, perpendicular on the same plane of the screw profiles, wherein an intersecting point of the rotational axis of the generating screw profile with the same plane is designated as a point of rotation of the generating screw profile and an intersecting point of intersection of a rotational axis of the generated screw profile with the same plane is designated as a point of rotation of the generated screw profile, the method comprising the steps of selecting, in step 1, the number of circular arcs n of the generating screw profile such that n is an integer greater than or equal to 1, selecting, in step 2, an outer radius ra of the generating screw profile such that ra is greater than 0 (ra>0) and less than or equal to the centre distance of axes a (ra≦a), selecting, in step 3, an inner radius ri of the generating screw profile such that ri is greater than or equal to 0 (ri≧0) and less than or equal to ra (ri≦ra), arranging, in step 4, the circular arcs of the generating screw profile according to the following configuration rules, such that: selecting, in step 5, a size of a first circular arc of the generating screw profile, that is fixed by an angle α_ selecting, in step 6, sizes of additional n−2 circular arcs of the generating screw profile, that are defined by angles α_ wherein the size of a last circular arc of the generating screw profile, that is fixed by angle α_n and radius r_n, is provided by a sum of the n angles of the n circular arcs of the generating screw profile in radian measures being equal to 2π, wherein angle α_n is, in terms of radian measurement, greater than or equal to 0 and less than or equal to 2π, wherein the radius r_n closes the generating screw profile, wherein the radius r_n is greater than or equal to 0 and less than or equal to the centre distance of axes a and the position of the last circular arc of the generating screw profile is fixed corresponding to said configuration rules, and wherein the n′ circular arcs of the generated screw profile are produced from the n circular arcs of the generating screw profile by