METHOD OF SCREW ELEMENTS MANUFACTURING Russian patent published in 2014 - IPC B29C47/40 

FIELD: machine building.

SUBSTANCE: invention relates to the method of manufacturing unspecified flat self-cleaning screw elements with tight mesh. Technical result is reached by the method of manufacturing unspecified flat self-cleaning screw elements with tight mesh, rotating in one direction; at that the screw generating profile and the screw generated profile are located in the same plane. The rotation axis of the screw generating profile and the rotation axis of the screw generated profile in each case cross the plane of the screw profiles at a right angle. Step1 involves choosing the number of circular arcs n of the screw generating profile. Step 2 involves choosing the outer radius ra of the screw generating profile. Step 3 involves choosing the inner radius ri of the screw generating profile with the ri≤ra. Step 4 involves setting of the circular arcs of the screw generating profile so that all the circular arcs pass into each other tangentially to form a closed convex profile. Every circular arc of the screw generated profile is placed inside or at the border of the ring having the outer radius ra and the inner radius ri with its centre being in the centre of rotation of the screw generating profile. At least one circular arc of the screw generating profile touches the outer radius ra of the screw generating profile. At least one circular arc of the screw generating profile touches the inner radius ri of the screw generating profile. Step 5 implies that the value of the first circular arc of the screw generating profile specified by the angle α_1 and the radius r_1 is chosen so that the angle α_1 in radians is more or equal to 0 and less or equal to 2π, and the radius r_1 is more or equal to 0 and less or equal to the centre-to-centre distance. Step 6 implies that the values of the further circular arcs of the screw generating profile specified by the angles α_2, …, α_(n-1) and radii r_2, …, r_(n-1) are chosen so that the angles α_2, …, α_(n-1) in radians are more or equal to 0 and less or equal to 2π, and the radii r_2, …, r, (n-1) are more or equal to 0 and less than the centre-to-centre distance. The number n′ of the circular arcs of the screw generated profile is formed from the number n of circular arcs of the screw generating profile by the fact that the number n′ of the circular arcs of the screw generated profile is equal to the number n of the circular arcs of the screw generating profile. The outer radius of the screw generated profile ra′ is equal to the difference produced by deduction of the inner radius ri of the screw generating profile from the centre-to-centre distance a (ra'=a-ri), and the inner radius of the screw generated profile ri′ is equal to a-ra.

EFFECT: provision for creation of unspecified profiles of screw and transition elements with tight mesh, simplification of manufacturing of such screw elements with no need in complex calculations.

12 cl, 216 dwg