Valve for fuel injector of IC engine - has sealing zone restricted by two parallel edges

摘要

The valve of a fuel injector for an internal combustion engine consists of a valve head (12) sliding in a cylindrical body (10). A spring presses the valve head (12) onto the seat (13) to seal off the orifices (15). The valve is opened by the pressure of the fuel supplied through the passage-way (16) acting on the underside of the valve head. A shallow groove (14) is formed in the conical surface of the valve head so that so parallel sharp edges are formed. When the valve is closed these edges form a seal on each side of the orifices (15). The edges can deform under the sealing pressure to accommodate dimensional inaccuracies.