Fuel-injection device with pre-injection and main injection

摘要

Fuel-injection device with pre-injection and main injection in diesel internal-combustion engines, a high-pressure injection pump (10) feeding the main injection quantity to a main injection nozzle (21) and a hydraulic pre-injection auxiliary pump (18) being driven by the same pressure pulse. The pre-injection auxiliary pump (18) has a stepped piston (22), which is forced by a powerful return spring (24) into a starting position predetermined by a first stop adjustment arrangement (26); a second stop adjustment arrangement (27) determines the stroke covered under the action of the delivery pressure of the high pressure injection pump. By means of separate and where necessary common adjustments or stops co-ordinated with one another the pre-injection quantity and injection timing can be varied regardless of the load and engine speed. <IMAGE>