Needle-Spring Locking Device for Pump-Injector (Injector) for Internal Combustion Engines

摘要

Needle-spring locking device for pump-injectors (injectors) of diesels, in which in order to significantly increase the lift and closing pressures of the nozzle needle, the locking spring ( 17 ) is disposed in the central cavity of the body around the outer surface of the plunger's bushing ( 2 ) and is connected with the needle ( 14 ) via a transversal cross-arm ( 15 ) disposed in the plunger bushing ( 2 ). This allows for increasing the average diameter of the needle spring (17) from 1.2-1.4 cm to 2-2.5 cm, and the spring power from 35-50 kgf to 180-220 kgf, respectively. In this case, the lift pressure of the nozzle body ( 10 ) (when the needle diameter is 0.6 cm) can amount to about 1200 kgf/cm², and the closing pressure of the nozzle body ( 10 ) can amount to about 800 kgf/cm², which corresponds to maximum injection pressures of 2000-2500 kgf/cm, as required for ensuring greater fuel efficiency and lower exhaust smoke and particle matter emission in future diesels.