GB144846A - Improvements in or relating to safety supports for motor cycles and like vehicles - Google Patents

Abstract

144,846. Purdy, A. J. May 7, 1919. Safety wheels.-Relates to motor-cycles and like vehicles of the kind in which auxiliary supporting- wheels are adapted to be raised from or lowered on to the ground by means automatically con. trolled by the driving-mechanism. The in. vention consists in effecting the automatic operation of the safety wheels by pneumatic means. A pair of lateral wheels o are pivoted to the frame of a motor-cycle &c. and are controlled by an air-pressure system so as to be raised automatically from the ground when the machine is travelling fast, and similarly lowerec into contact with the road when the machine is running slowly or standing still. An air tank 3( is mounted on a transverse bar underneath the seat 7 and is supplied with pressure through a pipe 40 from a pump 39 driven through a clutcl from the motor. A pipe 28 connects the tank with the central passage 25 of a slide valve 23, 24, Fig. 4, the side ducts 26, 27 of which are connected through pipes 31, 33 with ports 20, 21, at the top and bottom respectively of two side cylinders 14. The slider 23 of the valve is controlled through a bell-crank lever 35 by a governor 36 driven through gearing 37 from the motor, so that at high speeds air pressure passes through the pipe 33 and forces the pistons 17 to the top of the cylinders thereby lifting the wheels 6 from the ground; whilst at low speeds air pressure is admitted to the top port 20 to force the wheels downwards and support the vehicle as shown in Fig. 2. The side wheels are supported by frames 4 pivotally mounted upon transverse shafts 2. The clutch connecting the air pump to the motor is controlled by means of a bell-crank preferably operated from the seat of the vehicle.