Patent GB-190119240-A (GB)
Title: Improvements in and relating to Motor Cycles
Inventor: LEMAN EMD LUDWIG
Filed: 1901-09-26
Granted: 1902-09-26
Abstract: 19,240. Leman, E. L. Sept. 26. Motor cycles ; driving-mechanism, variable-speed. Comprises chiefly the mounting of the motor so as to form part of the frame, improvements in the driving-gear, both that in the motor casing and in the rear-wheel hub, and magneto ignition apparatus. (1) Fig. 1 shows a side elevation, and Fig. 5 a horizontal section through the rear-wheel hub and the motor casing. The motor is placed in the lower angle of the frame, and the motor casing 1 and gear casing are combined with each other and with the frame so as to form a rigid structure. The frame tubes 6, 7 are furnished with shoulders, and are inserted in sockets in the motor and gear casing. They are then secured by cap-nuts c with or without the addition of pins. The saddle tube 7 is made to slide through the bracket d to facilitate building the frame, and is afterwards fixed. (2) The motor cylinder 3 may be disposed parallel to the tube 7 or vertically, but nearer this tube than the crank shaft, in order that the connecting-rod may act vertically on the engine crank-pin. The engine crank shaft 10 drives the rear wheel 13 through toothed gear 36, 12, hollow shaft 11, and chain-wheels 37, 38, a disconnecting friction clutch being provided at 53 in the form shown in Fig. 5. The flywheels 2 revolve in the opposite direction to the wheel 13 and thus exert no gyroscopic interference with the steering. The pedal crank shaft 4 passes through and is supported by ball bearings in the hollow shaft 11, with which it may be connected when desired for starting the motor by a ratchet clutch 43, 44. In this the pawls are retracted or allowed to protrude by the action of a ring operated by an arm 49, which is capable of slight angular movement relatively to the crank 5. This arm can be operated by the foot. The chain- wheel 37 is also free as regards backward move- ment but as regards forward movement, can be driven through ratchet clutches 40, 50 either by the hollow shaft 11 or by the pedal crank shaft 4. (3) Figs. 7 and 8 show a form of two-speed gear contained in the back-wheel hub. In this arrange- ment there are three concentric hubs, viz., an inner one 55, rigidly attached to the driving-chain wheel 38, an intermediate one 58, capable either of being held stationary by a brake drum 60 and strap 68 or of being driven through the pawl 64 by the inner hub 55, and an outer one 61, to which the wheel spokes are attached. In the outer hub are mounted bevel planet pinions 62 gearing with bevel-wheels on the two other hubs. When the inner hub drives the middle hub, the outer hub and the attached wheel rotate at the same speed as the chain-wheel 38 ; but, when the middle hub 58 is stationary, the outer hub and wheel rotate at half this speed. A ring 67 is provided to ensure that the tightening of the brake straps 68 shall disengage the pawl 64. (4) Ignition is effected by a magneto-electric inductor 22 actuated from the engine valve shaft. The armature may either be rocked by an eccentric 24 or may be rotated by an eccentric crank mechanism, the object in each case being to obtain a variable action with the most rapid movement at the moment when the spark is produced. The interruption of the circuit to produce the spark is effected by a cam 26<1> which acts on a rod 26, and in order to enable the spark to be accelerated or delayed, the cam 26<1> is made adjustable on the shaft 25. The adjustment is effected by the differential gear shown in Fig. 4. The shaft 25 drives the eccentric 24 and the cam 26<1> through the bevel - pinions 33, 32, 34, the middle one 32 being mounted so that while running its position can be changed by shifting the arm 35. The result of adjusting this arm is to advance or retard the ignition cam and eccentric relatively to the valve shaft 25.