Abstract: A high-speed switch machine for actuating railroad switch points. The machine has an electric motor which drives a hydraulic pump. The pump supplies pressure fluid to a hydraulic cylinder adapted to move the switch points from an initial to a second limit position. A four-way, two-position hydraulic control valve directs fluid to the cylinder such that the cylinder automatically operates in an extension and retraction cycle. The uni-directional motor and two-position control valve minimize response times of the actuating components so that the switch points are thrown in a short time period.

Abstract: An accumulator comprising a cylinder and piston in which the front end of the piston is characterized by two spherical zones separated by a chordal zone while the opposed end wall of the cylinder is concave having a slope substantially the same as said chordal zone; the piston seal is an elastomeric ring supported on each side.

Abstract: A hydraulic system having a plurality of motor driven pumps in parallel legs, at least one being active and one in reserve, so combined with sensors to sense pump efficiency and filter efficiency that a condition deemed pump failure or filter failure results in activating the reserve leg and deactivating the inefficient leg. Other sensors detect flow meter failure and establish warnings of conditions deemed near-failure. The system may be duplicated both on the pressure side and return side of the pumps.The system reservoir is characterized by a tank for return fluid to be cleaned and a separate tank for the fluid to be delivered under pressure; so constructed as to (a) remove turbulence, (b) prevent vortex overlap, (c) remove silt fines and (d) maintain a proper pumping level.

Abstract: A hydraulic system having a plurality of motor driven pumps in parallel legs, at least one being active and one in reserve, so combined with sensors to sense pump efficiency and filter efficiency that a condition deemed pump failure or filter failure results in activating the reserve leg and deactivating the inefficient leg. Other sensors detect flow meter failure and establish warnings of conditions deemed near-failure. The system may be duplicated both on the pressure side and return side of the pumps. The system reservoir is characterized by a tank for return fluid to be cleaned and a separate tank for the fluid to be delivered under pressure; so constructed as to (a) remove turbulence, (b) prevent vortex overlap, (c) remove silt fines and (d) maintain a proper pumping level.