US 6,050,475 A · Method and apparatus for controlling downforce during friction stir welding

Abstract

The present invention provides a friction stir welding device for optimizing the depth of a friction stir welding tool in a workpiece. The welding device includes a spindle and a welding tool in rotatable communication with the spindle. The welding device also includes an inner housing defining an aperture through which the welding tool at least partially extends. Preferably, the inner housing has a plurality of cam followers. The device also includes an outer housing defining an aperture for at least partially receiving the inner housing. The outer housing has a base member and a riser that is rotatably mounted to the base member and that defines a plurality of inclined surfaces upon which the plurality of cam followers ride. The welding device includes a sensor in electrical communication with a controller for measuring the magnitude of force exerted by the welding tool upon the workpiece. In one embodiment, the welding device includes a motor and belt drive assembly responsive to the controller and in operable communication with the riser to modify the depth at which the welding tool is inserted into the workpiece and, correspondingly, the force exerted by the welding tool upon the workpiece.

Claims12

Dependent claims

An apparatus for attachment to a rotatable spindle for controlling the force exerted by a friction stir welding tool upon a workpiece, comprising:

an inner housing defining an aperture through which said friction stir welding tool at least partially extends, said inner housing having a plurality of cam followers;
an outer housing defining an aperture for at least partially receiving said inner housing, said outer housing having a base member and a riser, said riser rotatably mounted to said base member and defining a plurality of inclined surfaces upon which said plurality of cam followers ride;
means for measuring the magnitude of force exerted by the friction stir welding tool upon the workpiece;
and
means, responsive to said measuring means and in rotatable communication with said riser, for rotating said riser relative to said inner housing to thereby move the cam followers along the respective inclined surfaces so as to modify the force exerted by the friction stir welding tool upon the workpiece.

2 more elements

Dependencies are inferred from the claim text.

Method and apparatus for controlling downforce during friction stir welding

Life of this patent

Method and apparatus for controlling downforce during friction stir welding

Life of this patent

Abstract

Claims12