Patent GB-1397001-A (GB)
Title: Positive continuously constant gear-mesh speed change system  for planetary drive systems and the like
IPC: F16H37/08
Filed: 1972-05-11
Abstract: 1397001 Change-speed and clutch control L J KISS 11 May 1972 22005/72 Headings F2D and F2L A device for changing the motion, e.g. the speed-ratio between an input shaft 18 and a reaction member, such as a ring gear 16 in a planet train, to obtain correspondingly different speed-ratios between the input shaft 18 and a final output shaft 26, the change being positive and without power interruption comprises a mechanical alternator 50, continuously inputdriven and driving an output member continuously at a speed-ratio which is cyclically and continuously varied between the same limits as those provided between the input 18 and main output 26, the reaction member 16 being connected by a shifter system synchronously to the alternator output at the beginning of a ratio shift and accelerated or decelerated thereby to the new ratio condition during a dwell period in which the alternator sustains the whole torque of the input to output drive, the new ratio being then established positively and synchronously, and the alternator output disconnected from the reaction member. Control may be manual, or automatic by punched card or magnetic tape. Fig. 1, shows a basic train 10 and alternator 50, without the shift system, the heavy line repesenting neutral condition with the reaction ring 16 rotated idly reversely by the input-driven sun 24, whilst the output carrier 14 is stationary. Slidably plined on a ring gear shaft 32 is a selector member 36 which provides a reduction ratio when moved axially left to mesh its teeth 38 with stationary teeth 96, and direct drive, when moved further left to clutch its teeth 40 with internal teeth of a member 72 fast on the input shaft 18. Before reaching either of these ratio-establishing positions the teeth 36 of the selector 38 meshes with wheels 78, 76 respectively, the latter 76, fast on the output shaft 70 of the alternator 50, the former, 78, free thereon and driven thereby through a countershaft train 86, including a reversing idler 88. The alternator 50, continuously driven by the input 18, through a wheel pair 20, 58, comprises, in series, two crank-and-slot mechanisms 52, 56, connected by a radially offset intermediate shaft 62, the offset and gear ratios being so arranged that, during one revolution of the output shaft 70, the speed of the wheel 78 varies between zero and the reverse idling speed of the ring gear 16, whilst the speed of the wheel 76 varies between zero and the speed of the main input 18. The shift mechanism, described below, causes a shift to occur in three timed stages. In stage 1 at the precise instant at which the alternator driven wheel 76 or 78 is rotating at the same speed (including zero) as that of the selector 38, the selector 38 is meshed synchronously therewith. In stage 2 there is a dwell during which the alternator accelerates or decelerates the wheels 76 or 78 to the instant at which they are rotating synchronously with input 18 (for direct drive), or are stationary (for reduction), and in stage 3 the selector 38 is moved synchronously into mesh to establish the new ratio. The shift mechanism also establishes synchronously reduction drive from neutral, the ring gear 16 being decelerated from reverse to zero rotation for this purpose. Fig. 6, shows a complete embodiment including in series between a main input 176  and output 162 a main positive clutch brake 188, a direct-reduced stepped planet train 100 and a similar sun-ring train 102; the alternator 106, and shift-mechanism 108 mechanically operating the clutch-brake 188 and the positive direct-reduced selectors 140, 170 of the front and rear trains. With four ratios now provided, the alternator 106 is duplicated, having one output shaft 234, synchronizing the rear train 102, comprising an input-driven slotted wheel 194, crank 222, inner shaft 224, slotted arm 228, crank 232, and shaft 234; and another concentric output shaft 212 synchronizing the front train 100 and clutch-brake 188, comprising the slotted wheel 194, crank 200, sleeve shaft 202, slotted arm 206, crank 210 and shaft 212. The ratio selectors 140, 170 and main clutchbrake 188 are actuated by cams 280, 286, 274 on the shaft 260 of a mechanical relay, selectively turned through one revolution in one direction or the other, for upshift or downshift, by sliding a splined wheel 268 into mesh with two-toothed arms 248, 256, (Fig. 6G, not shown) on parallel shafts 244, 300 continuously oppositely driven by a wheel 184 on the main input shaft 176. Shift is initiated by energizing an upshift or downshift solenoid SA, SB, to slide the relay cam-shaft wheel 268 in the appropriate direction, the wheel being operated through a fork 270 which is returned by a cam 258 to neutral after the one revolution shift cycle. The twotoothed arms 248, 256 produce the two movements with intervening dwells to provide the three stages in the shift cycle above described. Limit switches LSA, LSB and LS-ST-C, are provided and are effective in a circuit, Fig. 6E, not shown, including relays and a manual rotary selector switch (M-SW), which, in addition to the four ratio settings, has a declutch and stop setting. After moving the rotary switch to the desired setting, an upshift or downshift sequence is initiated by depressing a further upshift or downshift switch-button (S-BV or S-BD). In Fig. 7, the reaction ring gear 360 of a single basic planetary train, having a sun 340 fast to an input shaft 336 and a planet carrier 352 fast on an output shaft 354, is selectively input driven at input speed or two reduced ratios through a stepped countershaft gear, or is held stationary for the lowest speed. The countershaft gear comprises a driven gear cluster on an axially slidable sleeve 370 splined on a sleeve extension 362 of the ring gear 360, the cluster gears being selectively meshed with wheels of a cluster on a countershaft 378 continuously driven by input 336 through a wheel pair 346, 386. One step leftward of the selector sleeve 370 from the neutral position, shown, meshes a wheel 372 with a fixed element 388 for first ratio; a second step meshes 372 with a countershaft wheel 382 for second ratio; a third step meshes wheels 374, 384 for third, whilst a fourth and final step engages the splines of the sleeve 370 directly with a splined member 348 fast on the main input 336 for direct drive fourth ratio. An additional freely mounted countershaft wheel 488, driven reversely by the wheel 382, produces, when meshed with the selector-sleeve wheel 372, a reverse motion of the reaction ring 360 which locks the final output shaft 354 positively stationary. Preceding each mesh, including that from neutral to first ratio, the meshing wheels are synchronized in stages as above described, by a preceding mesh with wheels driven by an alternator continuously input driven, and formed by three alternators in series; a first crank and slot 400, driving radially offset wheels 402, 408 synchronizing direct-drive and third ratio; a second comprising link-connected cranks 410, 414, on radially offset shafts 404, 416 (Fig. 7F, not shown), and a third, crank and slot 420, driving a wheel 432, synchronizing second ratio, and, through a reverse idler, a wheel 434, synchronizing neutral to first ratio. The timed shifter system, producing the three stages above described, comprises a transverse shaft 450, which drives, through bevels 472, a helically grooved drum 474, carrying a follower nut 480, secured to a shiftfork 482, which shifts the selector sleeve 370 axially. The transverse shaft 450 is turned, in the appropriate timed steps, by projections 488, Fig. 7D, not shown, on a continuously input driven disc 442, the steps being produced by axially shifting, in one direction or the other, by solenoids A, B, a drum 454 splined on the transverse shaft 450, and having teeth 468 or 469 thereby moved axially into the path of the disc projections 448. On termination of all the movement stages the drum 454 is axially returned to the central position, shown, by a camming central projection 444 on the driving disc 442. In Fig. 8, not shown, the input shaft 336 of Fig. 7, is driven in series through a dog-clutched countershaft reversing gear (502), providing direct drive which gives the four overall ratios above described; and a reduced reverse, providing three reduced overall reverse ratios and a standstill zero output, the latter replacing the output-locking assembly 488 shown in Fig. 7. In Fig. 9, not shown, there is an alternator constituted by a two-ratio planet gear having an input sun, output ring and reaction carrier, the latter driven by a slot and crank alternator. The output ring of this assembly can be used to produce selected minimum and maximum overall ratios for synchronizing planetary, spur or other types of positive drive systems. Fig. 10, not shown, is similar, but uses a bevel planet gear, to provide alternate forward and reverse at one-one output. Fig. 11, not shown, resembles Fig. 7, in having a basic three element train (580) directly connecting input and output, with speed ratio controlled by stationing and driving selectively, at different speed-ratios, the reaction ring gear (626), but here the first ratio is produced by holding the ring; the second and third by driving the ring through a fourelement stepped planet control train (582) producing two ratios by holding respectively the planet-carrier (664) and reaction ring gear (674); the fourth ratio, direct-drive, being produced by locking up the basic train by a clutch (620) and the control train by a clutch (676). Both the control train and the ratio alternator are input driven through a reducing gear (640) and the control train (582) drives the main reaction ring gear through an equal ratio step-up gear, so that the alternator rotates more slowly than the main gear. A dogclutched forward-neutral-reverse gear is provided in series at the output end. The various selector clutches and br