Patent GB-1034317-A (GB)
Title: Ratio selecting apparatus for a compound speed variator
IPC: F16H3/34
Filed: 1963-05-08
Abstract: 1,034,317. Variable-ratio gears; change-speed and clutch control. TOKHEIM CORPORATION. May 8, 1963 [May 21, 1962], No. 18287/63. Headings F2D and F2L. A change-speed control comprises ten predeterminer mechanisms 343-1 . . . 343-10 each of which can be preset to select a ratio so that ten ratios can be preselected from the thousand ratios provided by a variable-ratio gearing 131, a selector switch 539 being manually settable to select any one of the predeterminer mechanisms, and a switch 593 being actuated manually to close circuits engaging the preselected ratio. Variable-speed gearing.-The gearing comprises an input shaft 91 driving ten parallel shafts numbered 0 . . . 9 which are driven at speeds corresponding to their numbers, the shaft O being stationary, and each shaft having the sun gears of three epicyclic gears 253, 255, 257 fast thereon, and each epicyclic gear having stepped planets meshing an output sun, the suns of the epicyclic gears 253 being geared to a common gear 275 which is fast with the sun 277 of an epicyclic gear 279 which has stepped planets 281, 287 the planets 287 of which mesh a sun 289 which is fast with the input sun of an epicyclic gear 293 having stepped planets 281<SP>1</SP>, 287<SP>1</SP> and an output sun 289<SP>1</SP> which is geared to a final output shaft 137. The epicyclic gears 255 have output suns meshing a common gear 285 which forms the planet carrier of the epicyclic gearing 279, and the output suns of the gears 257 mesh a common gear 295 forming the planet carrier of the gearing 293. The reaction planet carriers of the epicyclic gears 253, 255, 257 are stationable by means of rings 299, 301, 303 each of which has a single tooth, and is rotatable to engage this tooth selectively with teeth formed on the planet carriers, thus only one epicyclic gear of each set 253, 255, 257 is operative for any one ratio. The ratios of the gears are chosen such that the epicyclic gears 253 correspond to tenths, the gears 255 to units and the gears 257 to tens and the arrangement provides for ratios from 0 to 99À9 at intervals of 0À1. Preselector mechanism. The rings 299, 301, 303 are adjusted by means of a shaft 317 having a gear 319 meshing the tenths ring gear 299. The ring 299 has a sector 315 fast thereon which sector meshes a gear 323 loosely mounted on the shaft 317 and fast with a gear 325 which meshes the units ring gear 301, the arrangement being such that one complete revolution of the tenths ring gear 299 gives one tenth of a revolution to the units ring gear 301. In a similar manner the units ring gear is fast with a sector 315<SP>1</SP> meshing a gear 329 which drives the tens ring gear 303 through one tenth of a revolution for each complete revolution of the units ring gear 301. A magnetic clutch 336 is engageable to connect the shaft 317 to a reversible electric motor 338. The circuits of the electric motor and magnetic clutch include switches 357-1 . . . 357-10 controlled by the predeterminer mechanisms 343-1 . . . 343-10, each predeterminer mechanism comprising three cams 369 respectively adjustable to any one of ten positions relative to shafts 56, 58, 60 which are driven respectively from the ring gears 303, 301, 299. Each cam 369 has a single notch 377 which in one position registers with the roller 413 of a cam follower device 399, the device 399 of the lowest order mechanism 349 having an arm 415 closing a corresponding one of the switches 357-1 . . . 357-10 except when the follower is allowed to rise into the notch 377. The second order mechanism 347 has an arm 421 on the follower device 399 which engages an arm 419 on the follower device 399 of the lowest order mechanism 349 to prevent the switch opening unless both follower rollers register with their respective notches; in a similar way the highest order mechanism 345 has an arm 427 on the follower device 399 which prevents the rise of the follower device 399 of the second order mechanism, thus the switch can only open when all the cam notches 377 register with the corresponding follower rollers. The mechanisms 343-1 . . . 343-10 can be set to any of the desired ratios, but they must be set in ascending order with the predetermined mechanism 343-1 set to the lowest ratio and the mechanism 343-10 set to the highest. Assuming that the gearing is in its zero ratio position a manual switch 552 is actuated to drive the electric motor 338 forwardly and engage the magnetic clutch 336. The shaft 317 is thus rotated to change the gear ratios, the ratio being indicated by a register 141 comprising three dials fast on the tens, units and tenths shafts 56, 58, 60. When the desired ratio is indicated the switch 552 is opened and the cams 369 of the mechanism 343-1 are set to open the switch 357-1. The other ratios it is desired to preselect are set on the corresponding predeterminer mechanisms in the same way. To select one of the preset ratios, a selector knob 437 is turned in the appropriate direction to select the desired one of the predeterminer mechanisms 343-1 . . . 343-10, rotation of the knob 437 rotating an arm 541 of the selector switch 539 to engage an appropriate one of contacts 543-1 . . . 543-10. The selector knob 437 is connected by means of a slipping clutch arrangement 479 to a cam disc which is moved to one of two positions according to the direction in which the knob 437 is rotated so that a switch 527 is actuated to a forward or reverse position to drive the motor 338 in forward or reverse according as to whether the gear ratio that is to be set is higher or lower than that existing. When the selector knob 437 has been set to select the desired predeterminer mechanism the switch 593 is then closed, completing circuits to the electric motor and the magnetic clutch so that the gear ratio is changed until the appropriate switch 357-1 . . . 357-10 is opened by its predeterminer mechanism when the desired ratio has been engaged. During gear shift a solenoid released catch 465 engages a notch in a disc 461 which is fast with the selector knob 437 so that a different predeterminer mechanism cannot be selected until the previously preselected ratio has been engaged. Two of the variable-ratio gears may be used, as described in Specification 1,017,511, in a null balance system to proportion the blend of a product, and another such variable-ratio gear may be used to compute the cost of the product as it is delivered.