NO. DISTRIBUTING VALVE WITH QUICK-ACTION CYLINDER CAP. RELEASE AND CHARGING POSITION. Fig. 18 represents the distributing valve with QUICKACTION CYLINDER CAP, with all operative parts in the released and charging position; the conditions that exist within the distributing valve are the same as were described in connection with Fig. 9 B, and are, presumably, well understood; the piping diagram of Fig. 9 A will also apply as an adjunct to this distributingvalve chart, and need not be reproduced. Referring to the quick-action cylinder cap, the graduating spring, 46, and the graduating stem, 59, appear, as in the plain cylinder-cap, except that stem 59 is lengthened and made to engage the emergency slidevalve, 48, between its shoulders; with the graduating spring relaxed within its limit, as shown, the slide valve covers port j in the seat, and brake-pipe air entering at BP only fills the slide-valve chamber of the cylinder cap, flowing thence into chamber p of the distributing-valve proper, and, as usual, through feedgroove u to the pressure chamber. The provision of passageway m that carries the brakecylinder air down to the lower part of the equalizing portion of the distributing valve is now seen to have MAIN BRAKE PIPE APPLICATION BRAKE APPLICATION FIG. 19.-No. 6 Distributing Valve with Quick-Action Cylinder Copyright, 1909, by The Norman W. Henley Publishing Co. been for the purpose of affording brake-cylinder pressure connection with the quick-action cylinder cap in the possible case of its use; passage m opens into the lower chamber under the rubber-seated, emergency check-valve 53, the check-valve being held to its seat in the absence of brake-cylinder pressure by the spring, 54. The intermediate chamber, x, is closed against either brake-pipe pressure or brake-cylinder air, now, and is therefore given no reference color. At graduated service applications, equalizing piston 26 moves only to contact with graduating stem 59, without compressing the graduating spring or moving the emergency slide-valve, and the brake-cylinder pressure can only fill the check-valve chamber of the cylinder cap; so that no unusual results are obtained, except from emergency applications. Emergency Position. Fig. 19 represents the distributing valve with quickaction cylinder cap in emergency position. When a sudden, heavy reduction of brake-pipe pressure is made, the effect on the equalizing and application portions of the distributing valve is precisely the same as was described with reference to Fig. 12 B, emergency position; but the full stroke of the equalizing piston, compressing the graduating spring in the quick-action cylinder cap, carries emergency slide-valve 48 with it and uncovers port j in the slide-valve seat; brake-pipe air from chamber p rushing down through port j fills chamber x where its pressure unseats the emergency checkvalve, 53, and flows to the passage, m, thence to passage c and the locomotive brake-cylinders through the pipe connecting at CYLS. This described action takes place at the instant piston 26 strikes the quick-action cylinder-cap gasket, and, as main-reservoir air can not flow to the brake cylinders until as the result of piston 26's stroke-pressurechamber air has filled application cylinder g and forced piston 10 to the right to unseat application valve 5it is obvious that brake-pipe pressure is the first to reach the brake cylinders; with the opening of the application valve the supplying pressures commingle in passage c as brake-cylinder air, which, when it becomes equal to the lowering pressure of the brake pipe, will permit check valve 53 to seat and prevent the brakecylinder air from flowing back to the brake pipe through the open port, j; and, as soon as the brake-cylinder pressure becomes as great as the pressure in the application cylinder, piston 10 will close application valve 5, this upper portion assuming the lap position in the same manner that has been described repeatedly before. Results from the quick-action cylinder cap produce no effect in the rest of the locomotive-brake equipment |