Patent GB-361902-A (GB)
Title: Improvements in and relating to machines for boring metal
IPC: B23Q5/02
Filed: 1930-05-22
Abstract: 361,902. Variable-speed and reversing gearing. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.-(Giddings & Lewis Machine Tool Co. ; 16, Doty Street, Fond du Lac, Wisconsin, U.S.A.) May 22, 1930, No. 15745. [Class 80 (ii).] An electric motor is connected by a belt drive and gearing to a vertical shaft 151, Fig. 3, having splined thereon a bevel gear 152 which drives a nine-speed change gear for the spindles of a drilling, milling, &c. machine. A shaft 156, Fig. 10, driven from the bevel gear 152, has freely rotatable thereon gears 160, 161 and splined thereon a gear 167 which carries clutches 165, 166 for engagement with the gears 160, 161. A second shaft 157, has rotatable thereon gears 168, 169, 170, giving three speeds to this shaft from the gears 160, 161, 167, and also gears 171, 172 which, through gears 173, 174 rotatable on a third shaft 158 and a combined gear and clutch 180 splined thereon give nine speeds to a pinion 216. A shaft 221, Fig. 3, coaxial with the shaft 158 and having an end bearing therein is driven by the gear 216 either directly through a clutch 223 or at a reduced speed through a back gear shaft 218 and a clutch 225. A further two-speed drive from the shaft 221 to the auxiliary spindle sleeve 148 is obtained by gears 227, 228 respectively rotatable on and splined to the shaft, a clutch 232 splined thereon, gears 229, 233 respectively secured to and rotatable on the sleeve and a clutch 235 splined thereon. The clutches 232, 235 are moved simultaneously to disconnect the spindle drive or connect to either of the gears 227, 228. A further gear 260 on the sleeve 148 drives the main spindle 140 through a gear 261 and a disconnectible clutch 263. A pinion 265, Fig. 3, on the auxiliary spindle sleeve 148 drives change-speed and reversing gearing which is connectible to the feed ram of either spindle. A shaft 267, Fig. 17, is driven by a gear 266 from the pinion 265 and has splined thereon a double gear 279, 280 and a single gear 281. A second shaft 268 has rotatable thereon gears 272, 274, 275 for selective engagement by the gears 279, 280, 281 and gears 273, 275, 276 for selective engagement by gears 284, 285, 286 splined to a third shaft 269, thus constituting a nine-speed drive for a pinion 323 on the shaft 269. A shaft 327 coaxial with the shaft 269 may be driven directly thereby through a clutch 329 or at a reduced speed through a back shaft 325 and a splined gear 330. The shaft 327 drives a shaft 351 either directly through gears 349, 353 or reversely through gears 348, 354, and an idler 350. Pick-off wheels 360 transmit the drive to a shaft 362 carrying a worm 363, Fig. 18, which engages a worm wheel 364 attached to a clutch element 365 having internal teeth on an annular flange 369. Two plungers 393 have complementary clutch teeth and are radially slidable in a drum 385 keyed on a shaft 383 rotatable within a sleeve 366 of the clutch element 365. A bevel gear 417 on the shaft 383 engages a bevel gear 418, Fig. 2, on a shaft 419 which has rotatable thereon a bevel gear 420 driving a shaft 434, Figs. 2 and 3, journalled below the auxiliary spindle ram 149 and having a pinion 435 engaging a rack thereon. A further shaft 422 journalled in the casing 143 coaxially with the shaft 419 carries a bevel gear 427 which rotates a vertical shaft carrying a pinion 429 engaging a rack 432 on the side of the main spindle ram 141. A clutch element 424 splined to the shaft 419 is engageable either with clutch teeth on the bevel gear 420 or with a clutch 423 on the shaft 422 to supply the feed to either spindle. The arm which controls the clutch 424 is connected by a sliding rod to the clutch 263 for driving the main spindle 138 so that the feed to this spindle will be disconnected when the rotation is stopped. Interlock means are also provided to prevent the fed mechanism from being operated unless the clutch 424 is connected to feed one or other spindle and to prevent connection of the feed to either spindle unless the other is in the fully retracted position, and comprise a pin 456 pressed by a spring 458 into contact with the face of the gear 447. The clutch rod 441 has two recesses 461 which lie behind the pin 456 when the feed is connected to either spindle and consequently allow the pin to be cammed into one of the recesses by the rounded edges of a groove 459 in the gear 447 when the feed is started, thus locking the feed to the particular spindle until it has again been fully retracted so as to cause the pin to be projected into the groove and release the clutch rod. Unless one of the recesses 461 lies behind the pin, retraction of the pin is prevented and the gear 447 cannot be rotated to permit the cam 448 to allow the feed clutch 365 to be closed. Hand feed is provided by a wheel attached to a shaft 463, Fig. 8, connected by a sliding coupling 464 to the worm-shaft 362. The clutches 164, 177, Fig. 10, for varying nine of the spindle speeds are actuated respectively by shoes 181, 182, Fig. 4, secured to slidable guide rods 183, 184 and carrying pins 185, 186 engaging levers 189, 190, the levers being oscillated by notched control rods 194, 196, the former through a rock shaft 191 and the latter directly. The control rods have further notches engaged by levers 198, 204, Fig. 9, the former being secured to a shaft 200 and actuated by rocking thereof, and the latter having a roller engaging a groove 202 in the lever 198 and being actuated by sliding movement of the shaft 200. A handle 212, Figs. 8 and 9, is pivoted to a sleeve 208 splined on the shaft 200 and serves to give both rocking and sliding movements to the shaft. A handle 255, Fig. 8, also capable of rocking in two directions at right angles operates similar mechanism for controlling the clutches 223, 232, Fig. 3, for giving thirty-six speeds to the spindles 138, 133. The shoe which engages clutch 232 also engages clutch 235 so that in a neutral position the drive will be disconnected from the spindles. The four movable elements 277, 278, 282, 283, Fig. 17, of the nine-speed spindle feed gear are controlled by four sliding rode 308 .. 311, Fig. 15, actuated by rotary cams 302, 303, and are thus interlocked to prevent improper meshing of the gears. The rods 308 .. 311 are slidable in longitudinal grooves in a bracket 296 secured to the cover 133 and carry pins engaging the cam grooves 304 .. 307. The cam 302 is rotatable by a handle, 321, Fig. 8, through a bevel gear 318 and carries a mutilated gear 317, Figs. 15 and 16, engageable with three sets of teeth on a gear 316 attached to the cam 303. The drum 303 is thus rotated one third of a revolution for each revolution of the cam 302, giving the nine-speed combinations required during three revolutions of the handle 321. The cam 303 is locked by concave portions 322 on the gear 316 engaging the plain portion of the gear 317. A handle 336, Figs. 4 and 8, oscillates a lever 334 to slide a control rod 382 for the back gear clutch 328, Fig. 17, of the feed gear. The handle 321 which controls nine speed changes for the feed of either spindle carries a pinion 341, Fig. 8, engaging a gear 340 with a 3 to 1 ratio. Four circular scales are provided on the face of the gear 340, two for each spindle, the scales being observable through two apertures 347 in a slide 345 connected to the handle 336 which controls the two-speed back gears, the apertures 347 exposing the scales appropriate to the setting of the back gears. The scales which indicate directly the rate of axial feed of each spindle for revolution thereof are comprised in two concentric rows, those for the two spindles being alternated in each row and the corresponding readings being located at diametrically opposite points of the gear 340. Since the ratio of the gears 260, 261, Fig. 3, connecting the two spindles is 3 to 1, the readings for the main spindle are three times as large as those of the auxiliary spindle.