Patent ID: 6814313
Filing Date: 2004-11-09
Classification: F02M

Abstract:
Fuel injector for an internal combustion engine; the injector (1) being provided with a valve body (6), which comprises a valve (7) capable of controlling the flow of fuel and a cylindrical, tubular container (14) comprising a central cylindrical cavity (15), and with an electromagnetic actuator (5) to operate the valve (7); the valve body (6) furthermore comprising a sealing element (18), which is arranged so as to close a lower end of the tubular container (14) and is provided with a multihole atomiser (26) and a valve seat (17), and a plunger (16), which is capable of occupying the valve seat (17), is accommodated in sliding manner within the tubular container (14), and is set in motion by the electromagnetic actuator (5) in order to open and close the injector (1); the sealing element (18) being composed solely of a cylindrically symmetrical main body (27), which comprises the valve seat (17) and ensures fluid-tight closure of the lower end of the tubular container (14), and of a perforated disc (28), which is welded coaxially to the main body (27) and defines the multihole atomiser (26) in conjunction with an underlying truncated conical surface (29) defined in the main body (27); the electromagnetic actuator (5) comprising a fixed coil and a mobile cylindrical armature (10) that is attached mechanically to an upper part of the plunger (16); an upper guide of the plunger (16) being defined by the armature (10) and a lower guide of the plunger being defined by the atomiser (26); the injector (1) being characterised in comprising an internal channel (8) through which the fuel is supplied to the valve seat (17); the internal channel (8) being completely occupied by the armature (10), which comprises at least one supply through-hole (20) for passage of fuel towards the valve seat (17) and is provided with an antirebound device (21) of the hydraulic type; the valve seat (17) comprising a central hole (32), which is occupied by the plunger (16) and opens into an injection chamber (33) comprising a number of free injection through-holes (34), which define an injection nozzle (3).