Abstract: An insulated fuel injection device, particularly for diesel engines, is provided for maintaining the nozzle spray hole temperature at a reduced level during engine operation whereby coking at the nozzle hole is prevented. The device comprises an elongated injection nozzle having a spray hole at one end thereof and an elongated hood covering the nozzle. The hood has a spray orifice therein which is aligned with the nozzle spray hole when the device is assembled. The interior dimensions of the hood and the corresponding exterior dimensions of the nozzle are such that a generally annular gap is presented between the hood and the nozzle, at least in the vicinity of the hole, and a quantity of heat insulating material is disposed in the gap adjacent the nozzle spray hole and the hood aperture.

Abstract: An insulated fuel injection device, particularly for diesel engines, is provided for maintaining the nozzle spray hole temperature at a reduced level during engine operation whereby coking at the nozzle hole is prevented. The device comprises an elongated injection nozzle having a spray hole at one end thereof and an elongated hood covering the nozzle. The hood has a spray orifice therein which is aligned with the nozzle spray hole when the device is assembled. The interior dimensions of the hood and the corresponding exterior dimensions of the nozzle are such that a generally annular gap is presented between the hood and the nozzle, at least in the vicinity of the hole, and a quantity of heat insulating material is disposed in the gap adjacent the nozzle spray hole and the hood aperature.

Abstract: A piston, especially for internal combustion engines, which piston has a cup-shaped combustion chamber depression in the upper face wall, with recesses in the upper edge of the depression for a fuel injection nozzle and an ignition device, respectively. The fuel is injected into the cavity with a short unrestrained length of spray onto the depression wall, and during fuel injection combustion air is moved about an axis extending in the longitudinal direction of the piston. The combustion chamber depression has an at least nearly cylindrical wall in the region of the recesses, the first recess is formed by a trough which has sharp edges, terminates flat, and is inclined to a surface line of the depression. The other recess with which is associated the ignition device extends closely adjacent to the first recess, at an angle in the direction opposite to movement of air, with a ridge being provided between the two recesses.