Abstract: A snow making, multiple nozzle assembly is provided comprising a tubular casing having an upstream end wall and an outwardly bulging downstream wall containing a plurality of snow making, supersonic, air expansion and liquid atomizing nozzle orifices circumferentially spaced therearound with radially inwardly extending air grooves therebetween in the outer, bulging surface. A tube plate partitions the casing interior into an upstream water compartment and downstream air compartment, and for each snow making nozzle orifice contains a water jet nozzle for directing a water jet into a central portion of that snow making nozzle orifice. Pressurized water fed into the water compartment causes water jets in each of the snow making nozzle orifices while pressurized air fed to the air compartment causes a jacket of air to surround the water jets entering the snow making nozzle orifice. The water exits from the snow making nozzle orifices as fine droplets which form into snow.

Abstract: A railroad switch, snow deflecting apparatus is described in which air is fed through conduits to primary nozzles for directing air along the rails and towards the switch points to a position adjacent the apex of the switch. Secondary nozzles are spaced from the primary nozzles and behind the switch points so as to direct air along and between movable rails of the railway switch, and in the same direction as air from the primary nozzles to maintain the railway switch operationally free of snow.

Abstract: A control switch system for a railway switch heater with an environment probe near the switch and controlling switching on and off of the switch heater in a predetermined mode.

Abstract: An apparatus for producing snow deflecting air curtains for a railway switch comprising one (or two side-by-side) ducts along the center of the railway switch and having nozzle slits for directing snow-deflecting air curtains in opposite directions over each pair of rails consisting of one fixed and one movable rail. The duct internal cross-section tapers so that air passes therealong at a more or less constant velocity from an air blower connected to the conduit. The air curtains issue from the nozzle slits at at least one hundred feet per second and preferably travel along a path which inclines upwardly from the horizontal about 5.degree..