Patent GB-311474-A (GB)
Title: Improvements in and relating to the control of steam driven railway trains of the type known as "shuttle trains" and the like, fitted with vacuum brake apparatus
IPC: B60T13/46
Filed: 1928-02-20
Abstract: 311,474. Consolidated Brake &. Engineering Co., Ltd., and Rawlings, V. P. Feb. 20, 1928. Fluid-pressure.-Apparatus for the control of a steam driven shuttle train, equipped with vacuum brake apparatus, from a driving compartment remote from the locomotive comprises means associated with the vacuum brake apparatus whereby the driver can control the steam regulator valve of the locomotive and the brakes from this compartment. The vacuum brake ejector can also be controlled from this compartment. The ejector 5 and steam regulator 1 are mounted on the locomotive which is at the centre of the train and a driving compartment A is arranged at each end of the train. The regulator 1 is operated by a vacuum cylinder 4 connected by a pipe 21 to a valve 19 in the control compartment, which is adapted to connect the pipe 21 and the cylinder 4 to atmosphere to close the regulator 1, or to a constant vacuum pipe 20 to open the regulator. The pipe 20 is connected to the pilot jet of the ejector 5. An electrical indicator 32 adapted to show the position of the regulator 1 is operated by a contact maker 34 linked to the operating lever 3 of the cylinder 4 and adapted to vary the resistance 35 in the indicator circuit. The valve 19 is a disc valve having a spring-pressed member adapted to engage a notch in the middle or lap position, through which notch a lug on the handle is allowed to pass so that the handle can be removed when in this position. The cylinder 4 is similar to a standard separate chamber type vacuum brake cylinder but inverted. Air is withdrawn or admitted to the upper chamber, and in the lower chamber, which is closed, a partial vacuum is formed when the piston rises which assists its return. A non-return valve may be provided in the lower chamber to permit air to escape. The brake valve 12 comprises a casing 63, Figs. 8 and 10, divided into four chambers 66 connected at 14 to the train pipe 9, Fig. 1, two chambers connected respectively to a vacuum reservoir 15, Fig. 1, and the ejector control pipe 17 and a chamber 71 connected to atmosphere. A port from each of these chambers opens at the valve seat on which is arranged the rotary valve member 64, the interior of which is open to atmosphere through holes 78, and a large port on the valve face communicates with this interior. By means of cavities 81 the rotary valve is adapted to connect the ports of the valve seat, so that at position 100, neutral position, all ports are closed. At position 101, release position, the vacuum reservoir 15 is connected to the pipe 17 leading to a cylinder 6 which operates the steam valve of the ejector to evacuate the train pipe and release the brakes. At position 102, running position, the cylinder 6 is connected to atmosphere to reclose the ejector steam valve, and the reservoir 15 is connected to the train pipe. At position 103, or lap position, all ports are closed,. except those connecting the ejector control pipe 17 to atmosphere. At position 104, or serviceposition, the train pipe port 73 is brought into partial registration with the atmospheric port in the valve member 64 to apply the brakes, and in emergency position these ports are brought into full registration. The movement of the valve is limited by a fixed stud 83 adapted to engage lugs 87, 89 on the valve member, which is locked in the neutral position by a spring bolt 84 and is held in positions 102, 103, 104 by a spring pressed member 90 adapted to engage recesses 92 in the valve body. A vacuum horn 24, Fig. 1, connected through a vacuum reservoir 25 and a non-return valve 30 is sounded by means of a control valve 27. The steam regulator control cylinder 4 and also the cylinder 6 may be, similar to a standard vacuum brake cylinder, with both sides normally under vacuum.