Abstract:
A method of forming a hydrostatic nut (36) that cooperates with a lead screw (38) for translating a cam grinder wheel head (26). An externally threaded lead screw master (66) is inserted into an internally threaded cylindrical mold (50). Beads of wax or tape (76, 78) are adhered to the external threads on the standard (66) while the rest of the standard (66) is treated with a release coating to define a continuous cavity (86, 88) between the internal threads of the nut (36) and the external threads on the standard (66). An epoxy resin is introduced into the cavity. The standard (66) is then removed and the wax or tape (76, 78) is removed to leave oppositely directed helical channels (86, 88) in the polymer. The helical channels are pressurized with a thin fluid film that prevents metal to metal contact.
Abstract:
A spindle, comprised of a spindle body (68) and an indexing fixture (29), is configured to retain, and rotatingly drive, a crankshaft (10) relative to a grinding tool, so that each pin (16) on the crankshaft (10) is ground with a high degree of precision. A coupling mechanism (174), such as a pair of jaws (190, 192) with complementarily shaped teeth, is interposed between the spindle body (116) and the indexing fixture (29). Pressure is applied to one side of the coupling mechanism so that the jaws are normally engaged and the spindle body (116) and the indexing fixture (29) rotate as a unit. Motive power is supplied by a servomotor (98) secured to a primary drive shaft (100), which is joined to a secondary drive shaft (88), through an offset coupling (122), to define a motorized spindle.
Abstract:
A linear actuator divert switch (54), a limited angle motor driven divert switch and a limited angle motor driven cross-over switch (410) are provided for sortation conveyors (40). The divert/guide pins (25) on package diverters are formed with a generally football shaped cross-sectional configuration (252) to facilitate passage thereof through the various switches.
Abstract:
A method and apparatus for grinding crankshafts or similar devices in which one of the crankpins of the crankshaft is machined and subsequent to this machine step, the actual dimension of the crankpin is measured. This measured value is compared to the projected value of the crankpin and the distance of travel of a grinding wheel in-feed is adjusted accordingly.
Abstract:
A variable volume coolant system (42) for delivering liquid coolant. A first conduit path (46) is defined between a source of liquid coolant and a nozzle (40) for delivering coolant to the gap defined between the machine tool (34) and the workpiece (22); a second conduit path (48) is also defined between the source of liquid coolant and the nozzle (40). A first valve (52) controls the flow of liquid coolant through the first conduit path (46), while a second valve (54) performs the same function for the second conduit path (48). The first conduit path (46) possess a greater volume than the second conduit path (48). By selectively adjusting the first (52) and second valves (54), a high volume flow of liquid coolant is maintained over most of the machining operation.
Abstract:
A work drive orienting system (20) for a machine tool comprises a head stock (71) and a tail stock (49) for supporting the workpiece (W) to be machined, a locator (100) retained by a spider (90) in the head stock chuck (70), and a proximity sensor (106) located in the loader (60) operatively associated with the machine tool. The locating pin (P) of the workpiece has a predetermined angular relationship to the spaced eccentric portions of the workpiece. The proximity sensor (106) scans an approximately 70 degree arc on the workpiece, for the presence of eccentric surfaces, such as cam lobes. If no lobes are detected, the pin will be in a position to pass safely alongside the locator (100), and the chuck for the workpiece (W) may be engaged. If lobes are detected, the work drive spindle (82) must be angularly rotated relative to the workpiece (W), before the machine tool can accept the workpiece (W) with the projecting pin (P), and the chuck (70) can be engaged to clamp the workpiece (W) in the desired angular orientation.
Abstract:
A tapered bearing (306) for the drive drum assembly (100) of a belt grinding machine (10) that employs multiple, parallel, abrasive grinding belts (76), and back-up shoes (122) for pressing the belts (76) against the surfaces on a workpieces (46) to be ground. The drive drum assembly (100), in cooperation with small pulleys (120, 124) operatively associated with the contouring head (108), keeps the abrasive belts (76) properly trained. The central shaft (148) of the drive drum assembly (100) is secured between a fixed bearing support (160) and a laterally movable support bracket (142). A tapered bearing (306) is fastened to one end of the shaft, and a complementary shaped aperture (314) is defined in a spindle (312) retained in the movable support bracket (142). When the movable support bracket (142) is shifted inwardly, the tapered bearing (306) fits snugly into the aperture (314) so that the drive drum assembly (100) is supported in a rigid, sag-free manner. This "pre-loads" the drive drum assembly (100) and bearing assembly (330), so the assemblies rotate smoothly, without slippage. Seals (324) are provided about the tapered bearing (306) so that dust and debris cannot degrade the bearing (306), and the bearing (306) does not wear excessively, even under prolonged, high speed operation.
Abstract:
A grinding machine provided with a spindle (5) rotating under the influence of a cantilever mounted rare earth permanent magnet motor (40). Hydrostatic fluid film bearings (41, 42) are provided between the ends of the spindle (5) and a bronze bearing (64, 65) to support spindle (5) in such a manner so as to eliminate wear. A single oil reservoir (20) is used to supply oil to the hydrostatic bearings (41, 42), as well as to the cooling jacket labyrinth (17) of the motor (40).