Vought Aircraft Company

Ltv Aerospace & Defense Company

Michael J Wheetley

George A Earle, Iii

Richard D Button

David A Schaller

James W Shelby

A seam tracking robotic drilling machine (10) is disclosed which is capable of moving a drill head along the seam (12) between abutting skin panels (16, 18) to drill a plurality of precisely positioned holes (18) through the panel. The machine (10) includes a perimeter support frame (20) which mounts a platform (36) for rotation about an axis (38) generally perpendicular the panels to be drilled. The platform supports a carriage (48) for movement along an axis 50 parallel the surface of the panels and in the direction of the seam while the carriage (48) supports an inner carriage (62) for movement along axis 60 perpendicular thereto. A drill head (74) is mounted on the inner carriage (62). A series of variable height vacuum cup assemblies (22-28) support the perimeter support frame (20). A similar series of variable height vacuum cup assemblies (66-72) support the inner carriage (62). When one set of vacuum cup assemblies is activated for attachment to the panels, the other set is deactuated to allow the machine to walk along the seam.

Seam tracking drilling machine

A manually positioned computer controlled drilling machine (10) is disclosed for drilling a hole (12) through a surface (14). The machine includes a base (16) which is supported on a counterbalanced suspension so that an operator can manually move and shift the machine on the surface to be drilled. Automatic adjustable legs (20-26) are biased outwardly from the base by low pressure air cylinders which allows the operator to tilt and move the base (16) relative to the surface (14). This allows the operator to position the drill bit (18) over the position where the hole is to be drilled and orient the drill bit perpendicular to the surface. Caliper brakes (38) are then activated to lock the legs in place. A number of suction cup assemblies (42-52) are then sequentially moved outward into contact with the surface. A suction foot (56) on each of the suction cup assemblies is adhered to the surface by a vacuum. A double acting cylinder (62) associated with each suction cup assembly is pressurized to pull the suction foot away from the surface without pulling the foot off the surface, forcing the fixed adjustable legs to press with counteracting force on the surface and provide a stable platform for the drilling operation.

Manually positioned computer controlled drilling machine

High pressure gas cutting process useful for drilling large numbers of holes in large surface area workpieces such as air frame components and the like. The procedure utilizes a cutting tool which has an internal fluid passageway extending through the shank portion thereof and terminating in at least one discharge port adjacent a cutting edge of the tool. As the cutting tool is rotated and advanced into the workpiece in the course of the cutting operation, a high pressure gas is supplied into the cutting tool passageway under an applied pressure of at least 500 psia. The gas, which may be an inert gas such as nitrogen, is discharged from the cutting port into the tool with an expansive cooling effect. The gas then flows outwardly through the hole and exits the hole with sufficient velocity to entrain and remove the drill cuttings from the hole. A liquid lubricant can be employed to prolong the life of the cutting tool. The lubricant is present in such small portions as to avoid the buildup of an identifiable liquid phase within the hole. The cutting tool is operated at a cutting speed of at least 2,000 rpm and a penetration rate of no more than 1 mil per revolution of the tool.

High pressure gas drilling

A tactile sensing tool positioning system for positioning a tool normal to the surface of a curved workpiece is disclosed. The tool positioning system of the present invention includes a steel frame for rigidly supporting a cutting tool having a longitudinal cutting implement, such as a drill bit or countersink bit. The steel frame includes a steel collar which is normal to the axis of the cutting implement and which supports a deformable ring of polyurethane or other resilient material. A plurality of aluminum cylinder positioning sensors are imbedded into the steel collar and surrounded by the deformable ring with one end of each aluminum cylinder positioning sensor contiguous with the exposed surface of the deformable ring. The axial loading experienced by each aluminum cylinder positioning sensor is measured by an associated strain gauge, and a quadrature circuit is then utilized to balance the forces on the aluminum cylinder positioning sensors and normalize the longitudinal cutting implement. In an alternate embodiment of the present invention two groups of aluminum cylinder positioning sensors are disposed in two separate planes both of which are normal to the axis of the cutting implement. By balancing the forces to determine arcs of equal loading, the longitudinal cutting implement with the surface of a highly curved workpiece may be calculated.

Growing community of inventors

Bedford, TX, United States of America

Michael J Wheetley