GB1208494A - Railway track brakes and accelerators - Google Patents

Abstract

1,208,494. Railway systems. KLOCKNERWERKE A.G. 27 Feb., 1968 [28 Feb., 1967], No. 9371/68. Heading B7L. [Also in Division F2] In an apparatus for regulating the speed of a railway vehicle hydraulic piston and cylinder units 5 are mounted in a railway track and the pistons 7 are connected with movable abutments 8 for contacting the wheels of the railway vehicles for the transmission of kinetic energy to the rolling stock when it is moving below a target speed and removing kinetic energy from the railway vehicle when it is moving at a speed above the target speed characterized in that the units are mounted in cavities in the sleepers 3 or cross-ties forming part of the track. The apparatus also comprises upwardly-open dish means 15 arranged around the piston-rod 7 for catching oil which leaks past the seal around the piston-rod and transferring the oil to a leakage oil duct 14 provided in a channel member 12 adjacent to the track housing, the leakage oil duct 14 and the supply and return ducts 10 and 11 for a number of sleepers. Fig. 4 shows a further embodiment of the invention wherein each piston of the piston and cylinder unit 5 is associated with a pneumatic pressure supply means 22a, a pneumatic pressure control valve means 22 and pressure converter 21 having a pressure converting piston with a larger (26) and a smaller (25) face defining respectively parts of chambers 27, 24 respectively for air and liquid such that the pressure-converting piston is arranged to be subjected to air under pressure coming through the supply line 22a and the valve means 22 on its larger face 26 and having its smaller face 25 connected hydraulically through lines 71 with the piston 7 of the piston and cylinder control unit. The pneumatic pressure control valve means 22 is connected mechanically by means of a spigot 77 with the pressure converting piston 26 for the opening of passage means in the valve to connect the supply line 22a with the larger face 26 of the piston when the latter is moved in the direction to decrease the volume of the chamber 27. A non-return valve 72 is provided in the line 71 and a choke 73 is connected in parallel to it, the non-return valve 72 being arranged to check flow of liquid from the piston and cylinder unit 5 to the smaller face 25 of the pressure-converting piston and to be open for flow in the reverse direction. A duct 78 opens into the chamber 27 to allow air to escape from the upper end of the chamber when the control valve is in the position shown through a choke valve 81 to atmosphere.