GB1192463A - Improvements in or relating to Apparatus for the Control of Brake Pipe End Cocks of Railway Vehicles - Google Patents

Abstract

1,192,463. Railway braking systems. COMPAGNIA ITALIANA WESTINGHOUSE FRENI E SEGNALI. 22 Aug., 1967 [10 Sept., 1966], No. 38693/67. Heading F2F. For automatically opening or closing the brake-pipe end cocks when coupling or uncoupling railway vehicles, each vehicle carries an air distributer with a piston which is pushed in by contact with the corresponding piston in the adjacent vehicle, whereby air from the brake pipe is admitted through the distributer to one of two chambers in a control cylinder to operate the end cocks. Fig. 4 shows the arrangement comprising a distributer D, two-chamber control cylinder C and auxiliary cylinder A. When the vehicles are uncoupled (Fig. 3, not shown), the cock R in the train pipe is closed and the pistons in units A and D are in positions such that the right-hand chamber of control cylinder C is vented to the atmosphere through line 17 and orifice 18 while the left-hand chamber is vented to the atmosphere through line 15 and orifice 16. On coupling (Fig. 4) the piston 10 is pushed in so that air from the brake pipe flows through lines 5 and 15 to the left-hand chamber of control cylinder C, pushing the piston to the right and opening the cock R through a slide 22 and pin 35. Air also passes into the auxiliary cylinder A with a delay due to restricted orifice 27 and moves piston 8 to admit air to the right-hand chamber of the control cylinder C via lines 4 and 17. The piston in the control cylinder C then returns to its central balanced condition. To uncouple (Fig. 5, not shown) lever 29 is operated to open valve 30 and admit air through line 31 to chamber 32, driving piston 33 to the left. This moves piston 10 to the left and vents the lefthand chamber of control cylinder C. The pressure in the other chamber drives piston 19 to the left to close the cock R, and after a delay the auxiliary cylinder A vents the righthand chamber through line 17 and restores piston 19 to its central position. In the next vehicle the piston 10 is driven inwards beyond its normal (coupled) position and similarly connects lines 5 and 15 in that vehicle. After uncoupling, valve 24 re-opens and chamber 32 is vented through orifice 37. If the vehicles did not in fact become separated, the operation can be cancelled by operating button 41 to vent chamber 32 through valve 40. The controls 29 and 41 are operated by the same handle which has a plurality of free and locked positions (Fig. 8, not shown). Breakage of hose 38 or 39 (Fig. 6, not shown) does not cause closure of the end cock R since venting of chamber 26 causes piston 9 to move to the left and disconnect line 17 from line 4. Accidental uncoupling, e.g. due to breakaway of a train (Fig. 7, not shown) causes evacuation of the brake pipe and hence venting of both chambers of the control cylinder C, so that the cock R remains open. Manual closing of cock R can be effected by operation of lever 29 even if the vehicles remain coupled; this is cancelled by operating button 41 as above. Modifications.-The pistons 10 of the two vehicles need not meet directly but can be connected by a flexible mechanical coupling (Fig. 9, not shown) so that the unit may be mounted beneath the car head. If a longer time can be tolerated for uncoupling, the valve 24, orifice 37 and valve 40 are omitted (Fig. 10, not shown) and evacuation of cylinder 32 is provided by a reservoir (42) with restricted orifice (43) to the atmosphere. The end cock can be opened or closed by direct manual operation of the slide 22.