Patent GB-719327-A (GB)
Title: Improvements relating to fluid pressure reciprocating ram systems for propelling rail track vehicles
IPC: B61J3/08
Filed: 1952-02-26
Abstract: 719,327. Propelling vehicles. WESTINGHOUSE BRAKE & SIGNAL CO., Ltd., and KERSHAW, N. G. Feb. 13, 1953 [Feb. 26, 1952], No. 5014/52. Class 103(3) [Also in Group XXX] . A fluid pressure double acting ram has its piston connected through a multiplying and reversing device to two pusher arm assemblies and the arrangement is such that the pusher arm assemblies are moved in opposite directions throughout each stroke a distance which is a multiple of the piston stroke, their strokes overlap and they are arranged to engage sequentially a vehicle or cut of vehicles to be moved along a railed trackway. Two trollies 3 each provided with pusher arms 4 are mounted on parallel I- shaped rails 7, 8 and 9 arranged between the rails 5 of a rail track and are connected to one another by cables or the like. 10, 11 one cable 10 of which passes round the pulley 12 and the other around a pulley 13. The pulleys 12, 13 are mounted on members adjustable along screened arms 20. One of the trollies is attached by a bracket 24 to a driving chain or the like 32 which passes over pulleys 30, 31 and is attached at each end to brackets 33 on a double acting ram cylinder 25. The pulleys 30, 31 are mounted on cross-heads at the end of piston rods 26, 27 of the double acting ram. When the ram moves the pulleys 30, 31 to the chain dotted positions I shown on Fig. 2, the arm 4 on the left hand trolley engages a rail waggon axle and pushes the waggon to a position A in which position the arm 4 of the right hand trolley, which is now in the position B, now engages the waggon axle to take over the drive when the ram and the trollies are returned to the initial position II. The arms 4 are normally held in the axle engaging position by a spring 6. When a vehicle is , to be passed in the reverse direction along the tracks 5 the ram is operated to move the pulleys 30, 31 to the position III in which position the arms 4 are depressed by means of cams 22 formed on their lower ends engaging fixed plates 23. The arrangement of the pulleys 30, 31 and chain 32 is such that the movement of the trollies is a multiple of the ram movement. As shown in Fig. 6, the apparatus is controlled by a three position valve 61. When the valve 61 is operated to the "AUTO" position; assuming the ram to be in position I, compressed air is supplied from a source M through a pipe 62 and pipes 57, 60 to open a valve 58 which valve on opening allows compressed air to pass from source M through pipes 59, 46 to an:open valve 45. The valve 45 allows air to pass through a pipe 44 a check valve 42 and a pipe 40 to the right hand side of the ram cylinder 25 to move the pulleys 30, 31 to the position II. On reaching position II a mechanism 55 is actuated to -open a valve 56 so as to allow compressed air to pass from pipe 57 to pipes 51, 47 to close the valve 45 thus cutting off the air supply to the right hand end of the cylinder 25 and to open a valve 52 thus allowing compressed air to pass from the source M through pipes 54, 53 to the left hand end of the cylinder 25 to move the ram and pulleys to the position I in which positions the mechanism 55 is again operated to close the valve 56 and the process is repeated. When the valve 61 is operated to the "LOWER" position compressed air passes from the source M through pipes 62, 49 to open a valve 48 which permits compressed air to pass from the source M through pipes 50, 43 the check valve 42 and the pipe 40 to the right hand end of the cylinder 25 to move the ram and pulleys to positions III. The valve 56 will not be effective when the mechanism is in position II with the lever 61 in the " lower " position since air will not pass through the pipe 57. '