GB253013A - A starting cock for pressure operated change-over devices for reversing the direction of flow in feed water pre-heaters of locomotives and the like - Google Patents

Abstract

253,013. Knorr-Bremse Akt.-Ges., and Juliusburger, P. Dec. 24, 1925. Multiple - way plug cocks.-A control cock for controlling the supply and exhaust of actuating fluid to power cylinders actuating valves for reversing a the direction of flow in feed water pre-heaters of locomotives and the like is provided with two intermediate relief positions in which all the pressure chambers are connected to atmosphere. The Figure shows two sections of the cock, the ports shown in the upper section control a double acting cylinder, while those in the lower section control a single acting cylinder. Pressure fluid is supplied through a conduit 2, and in the position shown passes through a groove in the plug to a port 6 in the liner leading to a conduit 6a connected to one end of the doubleacting power cylinder. At the same time the conduit 9<a> leading to the other end of the cylinder is connected to the exhaust pipe 13 through ports 8 and 9 and groove 12. At the lower section pressure fluid entering by the pipe 3 passes through slot 14 into a semi-circular slot 15 out of the plane of the section and thence through port 16, groove 19, port 25, conduit 24 to the conduit 23 leading to the single-acting cylinder. If the plug is rotated in an anti-clockwise direction the first relief position is reached when the groove 11 connects with the port 7. In this position conduit 6a is connected to exhaust through port 6, groove 11, port 7, and groove 10, while conduit 9<a> is connected to atmosphere through port 9 groove 12, and port 8. Conduit 23 is connected to exhaust through ports 20, 25 and groove 19. A continued anticlockwise movement brings the cock to the second relief position in which the ports in the upper section remain as before, but the conduit 23 is now connected to a second exhaust conduit 21<a> through ports 21, 22 and groove 18. In the final position pressure fluid is admitted to conduits 9<a> and 23 while conduit 6a is connected to exhaust.