Automatic double-flush riveting

Abstract

A method and apparatus for riveting together workpieces which, in their assembled relationship, have non-parallel exterior surface. Apparatus is provided for clamping the workpieces together between an upper clamp pad and a lower clamp pad, the lower clamp pad being mounted on a spherical bearing so that the lower clamp pad can conform to the workpiece surface. The lower clamp pad is provided with a conical aperture which can act as a pilot for tooling. The tooling is also mounted on spherical bearings so that when the lower clamp pad is in contact with the lower surface of the workpiece, and the tooling is moved towards the workpiece. The tooling will be piloted by the conical aperture to be normal to the surface. After the workpieces are clamped together, the workpieces are drilled from the upper surface and the upper surface is also countersunk. Then tooling is introduced through the lower clamp pad to countersink the lower surface about the drilled aperture with the centerline of the countersink on the lower surface being at right angles to the plane of the lower surface. Next, a rivet having a manufactured head is inserted into the aperture from the upper end and the lower end of the rivet is upset, the upper and lower riveting anvils which are used during the upsetting operation acting together in a vertical work line which is concentric with the centerline of the drilled aperture. Finally, the bucktail portion of the upset rivet, which extends beyond the lower surface of the workpiece, is shaved by a shaver piloted by the lower clamp in such a manner that the axis of the shaver is perpendicular to the plane of the lower surface to thereby provided a shaved aerodynamic surface.