Back to results
US 4,105,360 AGranted
Dual cut boring tool assembly
AssigneeR. H. Sheppard Co., Inc.
InventorDale L. Keller
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeR. H. Sheppard Co., Inc.
InventorDale L. Keller
Estimating the term…
A boring tool assembly performs both the rough and finish cutting operations upon a metal work piece without power activation or manual adjustments of the tool units between the cutting strokes. The assembly includes a boring bar having a pair of fixed, diametrically opposed rough cut tool units, and a pair of retractable finish tool units diametrically opposed to each other also. The tool units are automatically operative in response to either the rough cut or the finish cut of the boring tool assembly. Spring biased plungers normally pivot the finish cutting units toward their cutting positions. During the initial or rough cutting operation, forces act upon the heel of the finish tools causing retraction from the cutting position. This is possible due to the cutting edge configuration and angle of orientation of the tools, the positioning of the tools on the trailing side of the boring bar centerline, and the direction of advancement of the boring bar. When the rough cut has been completed, the finish tool units are forced to their outer cutting position across the center line of the bar and the reverse feeding of the tool assembly back through the work piece completes the dual cutting operation. The reverse direction of movement of the tool, the positioning of the cutting tip on the leading side of the center line, and the angle of orientation, preferably (10.degree.) to the axis of the boring bar, combine to effectively lock the finish tool units in position for efficient performance of the finish cut. Both the rough and finish tools are securely held in mounting blocks and adjustment of both is provided.
A tool assembly for performing rough and finish cutting operations on a workpiece having a curved surface by relative movement therewith comprising a tool support bar, first cutter means mounted on said tool bar for performing a rough cut along the curved surface, second cutter means mounted on said tool bar for performing a finish cutting operation along said curved surface, and means movably mounting said second cutter means for positioning said second cutter means alternately in a noncutting position during the rough cutting operation performed by the first cutter means and in a cutting position during the finish cutting operation.
A metal cutting tool assembly for machining a curved metal surface by relative movement therewith comprising a cutter having a cutting edge with a leading tip and a trailing heel, the cutting edge defining the thickness of said cutter extending between the tip and the heel, the thickness of said cutter being sufficient to allow engagement of either the leading tip or the trailing heel in a cutting and noncutting mode, respectively, but not both on said curved surface when positioned off-center with respect to said tool, and means for positioning said cutter in two off-center positions with respect to the cutting tool, whereby in one position a cutting operation is performed by the tip and in the other position a sliding engagement with said heel positions the tip in a noncutting position.
A boring tool assembly for cutting a circular bore in a metal workpiece during both forward and rearward axial movement in the bore comprising a tool support bar, first cutter means mounted on said tool bar for performing a rough cut along the curved surface during the forward movement of the tool assembly through the bore, second cutter means mounted on said tool bar having a leading cutting tip and a trailing heel for performing a finish cutting operation along the bore during the reverse movement of the tool assembly, said second cutter means being positioned off-center with respect to central axis of the tool assembly in the noncutting mode to provide engagment between the curved surface and the heel of the cutting tool, and the second cutter means being positioned off-center in the opposite direction in the cutting mode to provide engagement of the cutting tip with the surface of the bore, whereby the cutting tip is held out of engagement with the surface during the forward movement through the bore and is held in cutting engagement with the surface during the rearward movement through the bore.
Dependencies are inferred from the claim text.