Patent GB-190425374-A (GB)
Title: Improvements in and relating to Variable Speed Gearing applicable to Motor Road Vehicles
Inventor: BELDEN EDWARD HALE
Filed: 1904-11-22
Granted: 1905-02-09
Abstract: 25,374. Belden, E. H. Nov. 22. Motor road vehicles.- Relates to variable-speed gearing and stopping and reversing mechanism for motor road vehicles. The motor-driven shaft 5, Figs. 9 and 12, is connected with the motor shaft 2<11> by a conical friction clutch 6<1> which is normally spring-pressed into contact with the flywheel 2<1> of the motor shaft. The friction clutch slides on the ends of the shafts 5, 2", its hubs 6<11> and the end of the shaft 5 being connected by a key 5<1>. The hub 6<11> has a groove 6<111> to receive the upper end or fork of the arm 7", which i connected through a rocking shaft 7<1> with a foot-lever 7. The rear end of the shaft 5 passes through a bearing-box 16<1> of the variable-gear casing 16, and terminates in a disc 8 which has two or more circular rows of spurs, teeth, or pins fixed upon its face, and adapted to gear with the spur-wheel 10 of the transmission shaft 3. In a modification, the clutch and spur disc are fastened to the shaft 5 and move together. The shaft 5 is also connected with the lever 7 through a telescoping rod 21, connected at one end to the shaft 7<11>, and at the other to an operating- toggle 20 which is, in turn, connected with a lug 19<1> of the slidable barrel 19. The barrel contains roller bearings 18 for the shaft 5, and its lug 19<1> extends through a slot 16<11> of the bearing-box 16<1>. One or other of the links of the toggle is adjustable, and the forward end takes the form of an acute-angled bell crank, pivoted between lugs upon the box 16'. The telescoping rod 21 contains a spring 21<11>, and the parts of the rod are connected by a slot and pin 21<1>. The arrangements and dimensions of the parts are such that, when the foot-lever 7 is moved forwards, the friction cone 6<1> is first disengaged, and then the roller-bearing barrel, shaft 5, and gear disc 8 are retracted through the action of the rod 21. On release of the footlever 7, the clutch spring thrusts back the friction cone 6<1>, and hence the arm 7". The telescoping arm 21 then raises and straightens the toggle 20, by which means the disc 8 is driven back to mesh with the pinion 10, which is then in communication with the flywheel 2<1>. The middle pivot of the toggle is held against the bottom of the box 16<1> by the back pressure of the gear, this thrust being taken by the roller bearing 18 and an additional thrust bearing 18<1> on the shaft 5 at the end of the barrel 19. That part of the transmission shaft 3 which revolves in the hub 13<1> of the compensation gear case 13. held in roller bearings 17, is in two parts, each part 3<1> having a bevelled gear within the gear case connected by compensating-pinions. The several parts of the transmission shaft are connected by couplers 3<A>. The pinion 10 is mounted on the hub 13<1>, to which it is connected by a key 10<11> so as to be longitudinally adjustable. The pinion 10 is moved into engagement with the rows of teeth on the driving-disc 8 by means of a rod 12 slidable in a bearing 12<11> in the casing 16 and connected to the pinion by a collar 11. The rod 12 is preferably operated by a foot-pedal 23 rigidly attached to the rocking shaft 7<1>, which is connected to the rod 12 by a series of levers and arms 23'. The foot-lever 23 is returned by a spring when released. A pinion locking-device is employed to ensure exact engagement of the variable-speed gear members. A bolt 24, slidable in a bearing 25 in the gear casing 16, Figs. 12 and 14, has a jaw 24<1> which engages with the edge of the disc 8. The rod 12 has a number of holes 26 corresponding to the different positions of the shiftable pinion 10 to ensure proper meshing. Unless the pinion 10 is in one of these positions, the bolt 24 blocks the forward movement of the disc 8 to engage with the pinion. This arrangement also prevents manipulation of the variable-speed gear except when disconnected from the motor. A band-brake wheel 27, preferably arranged on one of the hubs 13<1>, is operated by a foot-pedal 29 through the band operating rod and levers 28. The engine or motor governor is preferably connected with the foot-lever 7, and, where variable-speed gearing is only used to increase the speed slowly, the spurred disc and pinion are supplemented by continuouslyengaged bevel gears 30, 31, Fig. 22. The gear 31 is of a greater diameter than the disc 8, and a clutch 32 is arranged between the pinion 10 and the gear-wheel 31. The pinion is arranged to be wholly disconnected from the disc 8, and at such times serves to connect the gear 31 to the transmission shaft 3 through the medium of the clutch 32. The teeth of the members 8, 10 are made on the principle that like curves, when rotated into contact about axes that are relatively perpendicular, engage and remain in rolling contact until the moment of departure, passing meantime through the stage of coincidence. The teeth 10<1> of the pinion 10, Fig. 18, are those of an ordinary single curve spur gear wheel but with bevelled edges and pointed teeth. The disc teeth 9, preferably of uniform size and form throughout, may have an elliptical cross-section, but are preferably circular. They have rounded ends, and have conical sides modified to fit the side curves of the pinion teeth exactly.