초록 ▼

A method of spin forming an open-ended container or other cylindrical metal workpiece by inserting a conically tapering mandrel coaxially therein and pressing the side wall of the workpiece against the inserted mandrel with plural symmetrically arranged forming discs while unidirectionally translati

A method of spin forming an open-ended container or other cylindrical metal workpiece by inserting a conically tapering mandrel coaxially therein and pressing the side wall of the workpiece against the inserted mandrel with plural symmetrically arranged forming discs while unidirectionally translating the workpiece, and independently translating the mandrel, relative to the forming discs.

대표청구항 ▼

1. A method of spin forming a hollow workpiece having an initially cylindrical side wall portion with an axis and at least one open end, comprising(a) disposing, coaxially within the side wall portion, a mandrel tapering conically in one direction from a region of maximum radius at which the mandrel

1. A method of spin forming a hollow workpiece having an initially cylindrical side wall portion with an axis and at least one open end, comprising(a) disposing, coaxially within the side wall portion, a mandrel tapering conically in one direction from a region of maximum radius at which the mandrel is in substantially 360.degree. contact with the side wall portion; (b) disposing a plurality of rotatable forming discs symmetrically externally around and in edgewise contact with the side wall portion at a location, along the axis, through which the mandrel extends, for pressing the side wall portion inwardly against the mandrel at said location; and (c) rotating the workpiece about the axis while (d) unidirectionally translating the workpiece, in the direction of taper of the mandrel disposed within the side wall portion, along the axis relative to the forming discs, (e) moving the forming discs radially symmetrically in maintained edgewise spin-forming contact with the cylindrical side wall portion at the aforesaid location to vary the radial distance of the discs from the axis, and (f) translating the tapering mandrel along the axis relative to the forming discs and the workpiece to vary the radius of the tapering mandrel at the aforesaid location concomitantly with the varying radial distance of the discs from the axis.