Abstract: A dual use roadway or railroad travel vehicle such as a railcar mover (10) which includes an inner set (24) of wheel assemblies (28, 30) designed for alternate roadway or rail travel, together with fore and aft rail wheel assemblies (32, 34) which may be alternately retracted for roadway travel or lowered for rail travel. The wheel assemblies (32, 34) each have a pair of rail wheels (36, 38) mounted spindles (48) so that the rotational axes A of the wheels (36, 38) are oriented at an oblique angle &agr; of less than 6° relative to the horizontal H; this wheel orientation, together with a rail wheel geometry including a rim surface (40, 42) parallel with the associated rotational axis A and a reduced radius of curvature R between the rim surface (40, 42) and the flange (44, 46), significantly decreases the problem of rail wheel climb encountered with conventional movers (10), while also reducing flange wear.

Abstract: A dual use roadway or railroad travel vehicle such as a railcar mover (10) is disclosed which includes an inner set (24) of wheel assemblies (28, 30) designed for alternate roadway or rail travel, together with fore and aft rail wheel assemblies (32, 34) which may be alternately retracted for roadway travel or lowered for rail travel. The wheel assemblies (32, 34) each have a pair of rail wheels (36, 38) mounted on fixed spindles (48) so that the rotational axes A of the wheels (36, 38) are oriented at an oblique angle &agr; of less than 6° relative to the horizontal H; this wheel orientation, together with a rail wheel geometry including a rim surface (40, 42) parallel with the associated rotational axis A and a reduced radius of curvature R between the rim surface (40, 42) and the flange (44, 46), significantly decreases the problem of rail wheel climb encountered with conventional movers (10), while also reducing flange wear.

Abstract: A power driver and method of pile driving. The invention encompasses a pile driver having a ram, cylinder and piston arrangement mounted in a framework, such arrangement being typical of those power drivers of the prior art. A compressible fluid, such as air or steam, enters into the cylinder through an intake port and leaves through an exhaust port. Both ports are controlled by a common valve. Expansion of the steam within the cylinder acts against the piston causing the piston rod to rise thus raising the ram and an associated slide bar. As the slide bar rises, it triggers the valve to move into a position effecting closure of both intake and exhaust ports. Further rising of the piston effects movement of the valve into a position wherein the intake port remains closed and the exhaust port is opened, thus exhausting the excess steam. Movement of the valve by elevation of the slide bar at each stage of movement is effected through triggering of cam followers or trips by cams on the slide bar.

Abstract: An automatic, fluid actuated, external control system for a pile hammer or the like is provided that can vary the operating stroke length of a pile hammer and that can be used to operate the pile hammer in either a continuous or single stroke mode. A series of axially spaced orifices in the hammer housing exhaust pressurized fluid from the housing in a sequence controlled by the position of the hammer piston within the housing. The orifices are coupled by conduit to a series of pressure sensitive valves external of the pile hammer. The pressure sensitive valves control the delivery and exhaust of pressurized motive fluid to and from the pile hammer in response to the position of the hammer piston within the hammer housing.