Piston

About: Piston is a research topic. Over the lifetime, 176135 publications have been published within this topic receiving 825412 citations. The topic is also known as: automotive piston.

Oil-free air compressor for rail vehicles

Abstract: An oil-free compressor for a rail vehicle includes a multi-piece compressor housing, a first piston cylinder supported in a first opening in the compressor housing, a second piston cylinder supported in a second opening in the compressor housing, and a multi-piece crankshaft assembly supported by the compressor housing. The crankshaft assembly is linked to pistons of the first and second piston cylinders by respective connecting rods. The connecting rods connect to a wrist pin associated with each of the pistons, and the wrist pins are respectively supported by a dry lubricant bushing to the associated piston. The compressor housing may have at least a first housing portion and a second housing portion. The first housing portion and the second housing portion may form respective halves of the compressor housing that are secured together with mechanical fasteners.

Lubricating system for engine

Abstract: An improved lubrication system for a two-stroke engine having a lubrication path from an oil sump directly to an induction valve assembly for noise reduction. The oil sump is divided into two chambers with a restricted passage therebetween to ensure lubrication of transmission gears upon startup while reducing drag during operation. A cross-drilled lubrication passage through each crankshaft throw terminates in a second passage proximate a dead-end plug, the second passage being in communication with the piston rod bearing. Each piston skirt includes at least one axial groove in registration with an oil supply passage. Circumferential grooves distribute the oil around the piston skirt from the axial grooves. The pistons may include ceramic top layers for heat insulation to increase the compression ratio possible by raising the ring positions. The engine incorporates an air/oil mixture separator within a balancer shaft chamber and air from the chamber is directed to the intake system.

Balancing device for a reciprocating piston engine

Abstract: The invention relates to the arrangement of a balancing device in a casing, for a reciprocating piston engine, which permits the evacuation of the lubricating oil. The device comprises two balancing shafts (7, 8) disposed in a main part (19) of the casing (11) and each fastened to one or two intermeshing pinions (21, 22) situated in an auxiliary part of the casing. A bottom oil passage (25a) provided between the two parts of the casing enables the pinions, acting as a draining pump, to fully drain the casing.

Time delay vent valve

Abstract: A self-actuated valve that functions after a predetermined time delay. The valve can be used to determine the time a fluid is at a point of use or to control the flow of fluid to or from a point of use. The valve can be self resetting. Basically, the valve assembly consists of a spool-shaped piston positioned in a chamber of a housing having a continuously interconnected inlet, an optional outlet, and an exhaust port. The larger end of the spool-shaped piston is acted upon by the pressure within an accumulator volume and the small end of the piston forms a seal, thereby normally closing the exhaust port from the inlet. The piston is provided with a flow restrictive means that communicates the inlet with the accumulator. The accumulator can be provided with an optional venting valve. The time delay vent valve works in the following manner. Fluid flows into or through the valve housing and passes through the piston''s flow restrictive means into the accumulator. Since the accumulator end of the piston has a larger area than the inlet end, the total force on the accumulator end of the piston will exceed the total force on the inlet end after a period of time. The force differential moves the piston, which opens the seal, and allows the fluid to flow from the inlet through the exhaust port. The time delay is readily changed by simply changing the flow restrictive means in the piston. The valve can be self-resetting or can be externally reset by several techniques.