Patent GB-695763-A (GB)
Title: Machine tools for machining articles having holed annular flanges and the like
IPC: B23B7/12
Filed: 1951-08-29
Abstract: 695,763. Drilling and turning wheel hubs; chucks. STANFORD-ROBERTS MANUFACTURING CO. Aug. 29, 1951 [Feb. 5, 1951], No. 20368/51. Classes 83 (ii) and 83 (iii). [Also in Group XXXVII] A machine tool for operating on workpieces having holed annular flanges such as wheel hubs 259 comprises a power-driven chuck 30, a stop block 206 on a rotary part of the chuck, a stop member 202 movable by motor means 198 into the path of the block, and control means for, operating the motor means. The machine tool, described ae a semiautomatic lathe, comprises transverselymovable slides 33, 37 on either side of the central chuck unit 30. The lathe bed, which is of arc-welded steel plate construction, carries the transverse slide 33 bearing longitudinally-movable tool slides 34, 35, the chuck unit 30, and a saddle 36 bearing a transverse slide 37. The chuck unit 30 comprises three jaws 93, Fig. 8, sliding in cylindrical bushed holes 71 in a member 64 rotated by a sprocket wheel 61. The jaws are controlled by wedge surfaces on a sliding ring 73 engaging T-slots in the jaws. The ring 73 is actuated by a yoke 106 pivoted at 109 to a hydraulic piston 104 and at 107 to the block 30, and connected at 112 to a non-rotating ring 81. The chuckrotating sprocket wheel 61 is driven by an electric motor 150, Fig. 12, which also rotates a plugging switch relay 156. Also mounted on the block 30, Fig. 13, are a tool-slide 145 reciprocated by hydraulic means 146 and a V-plate 161 bored with two holes 164 with which may be registered two holes 165 in the chuck member 64. For stopping the chuck, the switch device 202, Fig. 6, is lowered, by the air piston 198, to present an actuating roller 205 in the path of the adjustable cam-plate 206. The piston 198 is lowered when the plugging switch 156 is actuated and the momentum of the parts carries the chuck round until stopped by the switch 203. If, for any reason, the switch 202 is not positively actuated, a torque motor 153, Fig. 12, is energized to carry the chuck round to the correct position. The cross slide 37, Figs. 3 and 14, carries two tool holders 170, 171 and drilling and reaming units 221, 222, rotated by an electric motor 217. It is reciprocated by a piston 250 between stops 175, 176 and is located in the two intermediate machining positions by an air-operated plunger 182 engaging recesses in the base of the slide. Rods 223 extending from the units 221, 222 engage the aligned holes 164, 165 in the chuck to position the drills and reamers in relation to the work. Spring-pressed devices 224, Fig. 4, cushion the engagement of the units with the chuck and also support the toolspindles during machining. The drills are combined with countersinking means. The transverse slide 33, Fig. 4, is guided by a dovetail 227 engaged by gibs 230, 231 and by sidebearing surfaces 228, 229. The slide 33, Fig. 3, and the tool units 34, 35 are reciprocated by hydraulic pistons 236, 239, 242. For producing the wheel-hub 259, the slides 34 and 170 and a top slide 145, Fig. 8, are first advanced for roughing operations, slides 35 and 171 follow for finishing operations and the drilling and reaming units are then advanced successively. The drills and reamers are reversed before they are withdrawn. Each machine operation can be controlled individually by push-buttons or the machine may be operated semi-automatically. In the latter case, the operator first starts a hydraulic motor, a coolant motor and the drill motor. He then closes the chuck and operates the cycle start switch. The machining operations then follow automatically. When the work is finished, the operator opens the chuck. The hydraulic pistons may be replaced by worm or rack gearing rotated by electric motors.