Abstract:
A method and apparatus for machining a workpiece from a hardened unmachined part includes the use of non-rotating centers in a turning machine, on which the workpiece is mounted. The shape of the dead centers permits less force to be used in support of the workpiece for reducing friction between the rotating workpiece and non-rotating centers, while exerting a maximum amount of radial holding force to reduce runout in the machining operation. Lubrication can be supplied through the dead centers to further reduce friction and/or an anti-friction coating may be applied to the contacting surface of the centers for this purpose. Machining of the hardened part may be controlled by CNC equipment.
Abstract:
A centering guide cage apparatus for interior wall drilling includes a drill-bit holder, a flange bearing, a centering guide cage, a flexible casing, a hand-grip turnbuckle, and a flexible drill shaft. The centering guide cage, equipped with plurality of shape-memory supports, is terminally connected to an outer race of the flange bearing. The centering guide cage is terminally connected a distal end of the flexible casing from the opposite end. The hand-grip turnbuckle is terminally pressed against a proximal end of the flexible casing. A distal end of the flexible drill shaft is terminally connected to the drill-bit holder as the flexible drill shaft traverses through the flange bearing, the centering guide cage, the flexible casing, and the hand-grip turnbuckle. The flexible drill shaft is radially connected within an inner race of the flange bearing, wherein a proximal end of the flexible drill shaft is engaged with a drill driver.
Abstract:
A cutting insert comprises a rake face, a plurality of flank faces including clearance faces having a positive clearance angle. A cutting edge is formed at an intersection between the rake faces and the flank face and a convex wiper cutting edge formed on the cutting edge. A method for forming the cutting insert comprises the steps of placing a powdered material into a die and pressing the powdered material in the die to achieve a form having a convex portion on the rake face and at least one substantially flat clearance face having a positive clearance angle. Next, the form is removed from the die and sintered.
Abstract:
A dead center work support for a machine tool comprises a plurality, preferably at least three concentrically rounded raised radial projections defining the bearing surface of the dead center. The radial projections may be disposed either on the external or internal surfaces, which can be cylindrical, conical, or spherical. Between bearing surfaces a cut out section can be provided so that a cutting tool can run into the void to perform facing and turning of a center supported workpiece. Preferred embodiments comprise provisions for supplying lubricating oil through the tool to achieve continuous lubrication of the interface between the work and the center. The bearing surfaces may comprise hard, high-temperature resistant material, such as tungsten carbide, or ceramic.
Abstract:
A centering tool for rotary machine tools such as lathes and the like having axially aligned stocks comprising an end for engaging a workpiece in such a way that the engagement zone is substantially frusto-conical in configuration so that a workpiece having a centering recess disposed at an angle to the intended axis of the workpiece may be grasped so that machining can be accomplished about an axis in close proximity to the real axis so that a minimum of material is wasted.
Abstract:
A cutting insert comprises a rake face, a plurality of flank faces including clearance faces having a positive clearance angle. A cutting edge is formed at an intersection between the rake faces and the flank face and a convex wiper cutting edge formed on the cutting edge. A method for forming the cutting insert comprises the steps of placing a powdered material into a die and pressing the powdered material in the die to achieve a form having a convex portion on the rake face and at least one substantially flat clearance face having a positive clearance angle. Next, the form is removed from the die and sintered.
Abstract:
Workholding apparatus for mounting a workpiece (6) on a machine tool, the apparatus comprising a diaphragm chuck portion (2) and a tailstock portion (4). The chuck (2) includes a backing ring (70) with face portion (74) attached to the diaphragm (44) with the backing ring (70) having a centering locator guide (76) for centering and stopping the axial advancement of a workpiece in the chuck (2). The chuck (2) also includes a support ring (106) including material (109) located at the periphery thereof for sealing the area between the chuck and the workpiece and dampening vibrations brought about by the machining process. The tailstock portion (4) comprises a rotatable tailstock support (112) having at least one workpiece seating surface (117). The tailstock includes a centering locator guide (114) extending axially from the tailstock support (112) and having a generally curved outer surface (115) for centering the workpiece in the chuck (2). The tailstock portion (112) also comprises an outwardly flaring housing cover (118) including an end flange (124) and sealing means (126) whereby relative axial movement of the tailstock (112) toward the chuck (2) provides for the cover (118) to fit over a workpiece mounted in the chuck with the sealing means (126) contacting a surface of the workpiece radially inward of that portion of the workpiece being machined. The sealing means (126) preventing the introduction of contaminants into the workpiece (6) and chuck (2) and also providing for dampening of vibrations from the machining process.