Patent GB-189908657-A (GB)
Title: Improvements in Appliances for Automatically Operating Subterranean Railways.
Inventor: CARPENTER BENJAMIN FOWLER
Filed: 1899-04-25
Granted: 1900-02-24
Abstract: 8657. Carpenter, B. F., and Fowler, C. N. April 25 Pneumatic railways; points and switches; stations.-Relates to railways for underground service on which cars, driven by an air current or other means, are despatched from any one station to any other station on the line and are switched from the main line and brought to rest in the station by automatic means. The cars and a pusher for starting them are also described. Fig. 1 shows a general plan of a station and the up and down main lines in tunnels, one over the other. Each tunnel is connected to a separate fan d by inlet and outlet air drifts, and to the station yard by branch tunnels A', A<2>, a<2>, a<3>, the latter coming up to the level by an incline B'. To divert the car at any particular station, a wheel thereon is set to register with a switch-operating treadle m at that station ; a second treadle m<1> returns the switch R<1> and also opens air doors K, which are then closed by a third treadle m<2>. The cars are stopped by running into chambers O<4> closed at their ends by doors to act like a dash-pot, and then the cars can be removed to a turntable S and returned to the tunnels by pushers t arranged to give them sufficient initial speed. Pivoted dogs or pawls are placed between the rails to prevent the cars from running back. The construction of the vehicle and part of the switch gear is shown in Fig. 3. The roof of the car is in two hinged parts G, G<1> which are held down by flanges h on hinged end pieces H, and these are held by a T-bolt fastening. An airtight packing between the vehicle and the tunnel walls is made by a flexible strip at the top and sides and by flexible tongues or strips underneath. The vehicle has two axles, on one of which is mounted a laterally-adjustable wheel l, which can be fixed at any point indicated by graduations N so as to register with the treadle m at any desired station. The treadle is a long inclined bar pivoted at one end and connected to the switch tongues by cranks and links. A plan of the three treadles m, m<1>, m<2> is shown in Fig. 7, with the connecting-cranks and rodding for opening and closing the point tongues d and doors K and for returning the treadles to their raised position. The air doors K in the branch tunnel, and also those at the end of the stopping-chamber O<4>, have two leaves. The latter doors o', o' are opened by springs on their pivots when a locking-bolt p is removed by a lever p<1>, or are closed by the hand-lever Q acting through the links r and arms on the pivots. The car pusher is shown in Fig. 10. A piston T' attached to a trolley running on guide-rails w is driven along the cylinder T by air pressure controlled by the valve v, and it carries a pawl t<2> which engages the car. The valve is worked by the hand-lever u<3> and by the levers u<2> which are knocked over by tappets on the trolley in order to reverse the piston at one end or to cut off the air supply at the other end when the speed of the piston is less owing to the relief valve w<1>.