Patent GB-190417281-A (GB)
Title: Improvements in Valves for Air-Brake Systems.
Inventor: ALLISON CHARLES ARTHUR
Filed: 1904-08-08
Granted: 1904-09-29
Abstract: 17,281. Allison, C. A., [Levy, A. B.]. Aug. 8. Brakes, pneumatic-pressure. Relates to e ngineer's valves suitable for use with plain and quick acting, as well as for re - charging, triple valves on single cars or trains. Figs. 1, 4, and 7 are sections, the regulating- valve H being omitted in Fig. 4. Figs. 9 and 10 are plan and edge views of the main air valve, a n d Fig. 14 shows its seating. In the full release position shown, air or other fluid passes from the main-reservoir pipe B and chamber C through the passage 9<b> of the spring - supported main valve 9, and through the passage 17, which opens beneath the piston E in the chamber D, and establishes connection with the train-pipe G. Air is also admitted to the upper side of the piston through a branch 9<c> and the passage 19, from which there is also an outlet 20 for the attachment of the equalizing- reservoir. Air also passes through the ports 21<a>, 21<b> and passage 21 to the checkvalve chamber 22 and the chamber H<1>, whence it passes through the passages 27<a>, 17 to the trainpipe G. In the running position, the port 9 registers with the port 21<a> so that air passes from the main reservoir to the passage 21 past the check valve 23 and to the chamber H<1> and thence through the port 27<a> to the passage 17, chamber D, and train-pipe G beneath the piston E. At the same time, ports 9<d>, 9<b> communicate with ports 17<a>, 19<a> respectively, so that air passes from the passage 17 to the ports 9<d>, 9<b> through the passage 19 to the equalizing-chamber D<1> as well as to the equalizing-reservoir at 20 until a predetermined pressure obtains throughout the system, whereupon the diaphragm 24 and the regulating-piston 25 are forced down, enabling the check-valve 23 to descend and cut off further supply to the trainpipe. In the lap position, the valve H acts as a re charging valve, but, if re-charging triple valves are not employed, the port 9<f> is plugged, and all connection is cut off. The recharging port 9f, smaller than the port 9<e>, registers with the port 21<b>, and air passes in smaller quantity through the passage 21 into the chamber H' and through the passages 27<a>, 17 to the chamber D and trun pipe G. It also passes from the port 17<a> through the recess 9<g> to the part 19<b> and passage 19 to the equalizing-chamber D<1> and reservoir at 20. For service, the recess 9<g> connects the port 19<b> with the port 30<b> of the passage 30, which opens to atmosphere, thereby reducing the pressure in the chamber D<1>. The train-pipe pressure then raises the piston E which, being prevented from rotating by the guide-pins e<1>, turns the rotary valve F, which has an internal spiral groove F<1> to receive the pin E<2> of the piston spindle and is prevented from rising by the pressure in the chamber D. The train-pipe is thus opened to atmosphere by the ports f and passages 18<a>, 18<b>. The brakes are held by turning the valve to lap, in which case the air enters the equalizing-reservoir and the chamber D<1>, forcing down the pston E and closing the port 18<a> so that the train-pipe is re-charged. In the emergency position, a wide opening to atmosphere is given by the simultaneous registry of the passage 9<b> with both ports 17<a>, 30<c> and that of the recess 9<h> with ports 1 <c>, 30<a>.