Method of machining a workpiece between centers and a clamping device for performing this method
AssigneeIndex-Werke Komm.-Ges. Hahn & Tessky
InventorsHelmut F. Link, Erich E. Schafer
Life of this patent
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Abstract
A method for rough-turning and finishing a workpiece on a lathe wherein the lathe is provided with a tailstock center which is axially displaceable, a further center on the work spindle as well as axially displaceable front drivers and a chuck so that, for rough-machining, the workpiece is lifted off the work spindle center by means of the front drivers and driven by the chuck whereas, for finish-machining, the workpiece is held between the centers and driven by the front drivers.
Claims11
A method for machining a workpiece mounted in a lathe between a rotatable work spindle rotatable about an axis of rotation and having a chuck, front drivers and first center at one workpiece end and an axially movable second center mounted on a tailstock and urged in the direction of said first center at a second workpiece end, the second center being disposed substantially in alignment with the work spindle axis of rotation, comprising the steps of inserting a workpiece between the first and second centers;
- centering and supporting the workpiece between said centers;
- applying force to the workpiece end engaging the first center and removing the centered workpiece from engagement with said first center in the direction of said second center;
- supporting said workpiece between the point of force application and said second center;
- urging said second center to move substantially along said work spindle axis of rotation away from said first center;
- clampingly supporting the workpiece about peripheral portions thereof by means of said chuck;
- rotating the workpiece while so clamped to said chuck by rotatably driving said chuck;
- rough-machining the rotating workpiece;
- releasing the workpiece from the chuck while supporting the workpiece between said first and second centers;
- urging said front drivers against the end of the workpiece engaging the first center;
- rotating said workpiece by means of said front drivers while said workpiece is supported between said centers, and finish-machining the rotating workpiece.
A workpiece clamping apparatus for use in a lathe, comprising a work spindle rotatably driven about an axis of rotation;
- bearing means rotatably mounting said work spindle;
- a first workpiece center supportably mounted on an end portion of said work spindle;
- retractable front driver means supportably mounted on the spindle end portion;
- a tailstock spaced axially from said work spindle end portion;
- means for urging said front driver means into a retracted position wherein the distal ends of said front driver means are inwardly disposed of the distal end of the first workpiece center;
- an axially movable second workpiece center rotatably mounted on said tailstock;
- means for urging said second center toward said first center whereby a workpiece may be centered and supported between said first and second workpiece centers;
- a chuck mounted on said work spindle and having clamping jaws for clampingly engaging a workpiece after said workpiece is centered, and cooperative action with said second center in maintaining a clampingly engaged workpiece in substantial alignment with said axis of rotation;
- means for moving said clamping jaws in synchronism and concentrically to said axis of rotation into workpiece-engaging and workpiece-release conditions;
- said chuck clamping jaws moving at an angle to the work spindle axis of rotation when moving into engagement with a workpiece and being so located relative to said first workpiece center as to impart axial movement to a workpiece centered between said first and second workpiece centers whereby a workpiece is simultaneously driven from engagement with said first workpiece center, axially moved in opposition to the second center substantially along the workpiece axis of rotation and clamped into a position substantially coaxial with the workpiece axis of rotation;
- and means for extending said front driver means from the retracted position into engagement with the end of a workpiece when said workpiece is engaged by said first and second centers.
Dependencies are inferred from the claim text.