Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
207 words
In a fuel injector including an injector body (6), a nozzle (9), and shutter means (8, 28) closing said nozzle (9); an electromagnetic metering valve (40) for controlling said shutter means (8, 28) as to temporarily open said nozzle (9) said metering valve (40) comprising a valve head (56) having a drain conduit (63), and an electromagnet (42) having a magnetic circuit (46, 76) including a core (46), and an energizable coil (47) housed in an annular seat (48) in said core (46); an armature (43, 69) operable by said electromagnet (42), said armature (43, 69) including a circular disk (43) facing said core (46), and an axial stem (69) secured to said disk (43); said stem (69) being slidably guided by an axial guide element (87); a helical spring (89) provided between said element (87) and a washer (86) mounted on said stem (69) for normally causing said stem (69) to close said drain conduit (63); said armature (43, 69), said spring (89) and said washer (86) forming a preassembled assembly (43, 69, 86, 89); and a single fastening member (82) engaging said element (87) for fitting said assembly (43, 69, 86, 89) as a whole inside said injector body (6) independently of said electromagnet (42).
Claim 2
Dependent Claim
207 words
In a fuel injector including an injector body (6), a nozzle (9), and shutter means (8, 28) closing said nozzle (9); an electromagnetic metering valve (40) for controlling said shutter means (8, 28) as to temporarily open said nozzle (9) said metering valve (40) comprising a valve head (56) having a drain conduit (63), and an electromagnet (42) having a magnetic circuit (46, 76) including a core (46), and an energizable coil (47) housed in an annular seat (48) in said core (46); an armature (43, 69) operable by said electromagnet (42), said armature (43, 69) including a circular disk (43) facing said core (46), and an axial stem (69) secured to said disk (43); said stem (69) being slidably guided by an axial guide element (87); a helical spring (89) provided between said element (87) and a washer (86) mounted on said stem (69) for normally causing said stem (69) to close said drain conduit (63); said armature (43, 69), said spring (89) and said washer (86) forming a preassembled assembly (43, 69, 86, 89); and a single fastening member (82) engaging said element (87) for fitting said assembly (43, 69, 86, 89) as a whole inside said injector body (6) independently of said electromagnet (42).
Claim 3
Dependent Claim
75 words
A valve as claimed in claim 1, wherein said core (46) comprises a pair of coaxial annular pole pieces (72, 73); characterized by the fact that an outer pole piece (72) of said pair is shorter than an inner pole piece (73) of said pair and is fitted with a ring (76) substantially flush with said inner pole piece (73); the outside diameter of said disk (43) being smaller than that of said coil (47).
Claim 4
Dependent Claim
163 words
A fuel injector electromagnetic metering valve comprising an electromagnet (42) with a fixed magnetic circuit (46, 76) including a magnetic core (46), and with a coil (47) energizable so as to displace an armature (43, 69) for controlling the metering function; said core (46) comprising an annular seat (48) for said coil (47); said armature (43, 69) being in form of a disk (43) and comprising a stem (69) guided by an axial guide element (87), said disk (43), said stem (69) and said guide element (87) being preassembled to form an assembly; said electromagnet (42) being fitted to the injector body (6) by means of a threaded ring nut (44) external to said body (6); wherein said assembly is fitted inside said body (6) independently of said electromagnet (42) by a further ring nut (82) screwed inside a threaded seat (93) in said body (6); said further nut (82) having an inside, diameter greater than the outside diameter of said disk (30).
Claim 5
Dependent Claim
163 words
A fuel injector electromagnetic metering valve comprising an electromagnet (42) with a fixed magnetic circuit (46, 76) including a magnetic core (46), and with a coil (47) energizable so as to displace an armature (43, 69) for controlling the metering function; said core (46) comprising an annular seat (48) for said coil (47); said armature (43, 69) being in form of a disk (43) and comprising a stem (69) guided by an axial guide element (87), said disk (43), said stem (69) and said guide element (87) being preassembled to form an assembly; said electromagnet (42) being fitted to the injector body (6) by means of a threaded ring nut (44) external to said body (6); wherein said assembly is fitted inside said body (6) independently of said electromagnet (42) by a further ring nut (82) screwed inside a threaded seat (93) in said body (6); said further nut (82) having an inside, diameter greater than the outside diameter of said disk (30).
Claim 6
Dependent Claim
38 words
A valve as claimed in claim 3, characterized by the fact that said guide element is substantially in the form of a plate (84); said further ring nut (82) acting on a flange (90) of said plate (84).
Claim 7
Dependent Claim
29 words
A valve as claimed in claim 4, characterized by the fact that a calibrated washer (91) is provided between said flange (90), and a shoulder (92) of said body.
Claim 8
Dependent Claim
56 words
A valve as claimed in claim 4, characterized by the fact that said guide element comprises a sleeve (83) fitted to the end wall (87) of said plate (84); said end wall (87) presenting holes (88) enabling a chamber (60a) inwards of said plate (84) to communicate with a chamber (60b) outwards of said plate (84).