EP0385397A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Diesel engine electromagnetic fuel injector
Assignee: Elasis SCpA
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Filing: 1990-02-27
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Granted: —
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Expires: 2010-02-27
Abstract
Abstract An injector comprising a plunger (1) for controlling fuel passage between an injection chamber (3) and at least an injection orifice (4) formed in an injection nozzle (5); and an electromagnetic fuel metering valve (6) for controlling fuel passage through a drain orifice (7) between a control chamber (8), supplied with fuel under pressure, and a low-pressure chamber (11), so as to reduce the fuel pressure in the control chamber (8) to a given value and so displace the plunger; characterised by the fact that pressurized fuel is supplied to the injection chamber (3) and control chamber (8) by means of a single fitting (13) connected to a supply pipe (14) and coming out inside a supply orifice (15) formed in the injector body (2) and communicating with the control chamber (8) and a duct for supplying fuel to the injection chamber (3).
Inventors
- 👤 Sisto Luigi De Matthaeis
- 👤 Mario Sfarzetta
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 16:52
CPC Classifications
F; F02; F02M; F02M55/00; F02M55/004; F02M55/005; F02M47/00; F02M47/02; F02M47/027; F02M61/00; F02M61/16; F02B; F02B3/00; F02B3/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
220 words
1) - A Diesel engine electromagnetic fuel injector comprising: a plunger (1) sliding inside the injector body (2), for controlling fuel passage between an injection chamber (3), supplied with fuel under pressure, and at least one injection orifice (4) formed in an injection nozzle (5) secured to said body (2); an electromagnetic fuel metering valve (6) for controlling fuel passage, through a drain orifice (7), between a control chamber (8), supplied with fuel under pressure, and a low-pressure chamber (11), so as to reduce the pressure of the fuel in said control chamber (8) by draining the same through said orifice (7); surface portions of said plunger (1) being exposed to the fuel inside said injection chamber (3) and said control chamber (8), so that the pressures inside said chambers and acting on said surface portions displace said plunger (1) when the pressure in said control chamber (8) falls to a given value; characterised by the fact that said fuel under pressure is supplied to said injection chamber (3) and said control chamber (8) by means of a single fitting (13) connected to a supply pipe (14) and coming out inside a supply orifice (15) formed in said body (2) and communicating with said control chamber (8) and with a supply duct for feeding fuel into said injection chamber (3).
Claim 2
Dependent Claim
220 words
1) - A Diesel engine electromagnetic fuel injector comprising: a plunger (1) sliding inside the injector body (2), for controlling fuel passage between an injection chamber (3), supplied with fuel under pressure, and at least one injection orifice (4) formed in an injection nozzle (5) secured to said body (2); an electromagnetic fuel metering valve (6) for controlling fuel passage, through a drain orifice (7), between a control chamber (8), supplied with fuel under pressure, and a low-pressure chamber (11), so as to reduce the pressure of the fuel in said control chamber (8) by draining the same through said orifice (7); surface portions of said plunger (1) being exposed to the fuel inside said injection chamber (3) and said control chamber (8), so that the pressures inside said chambers and acting on said surface portions displace said plunger (1) when the pressure in said control chamber (8) falls to a given value; characterised by the fact that said fuel under pressure is supplied to said injection chamber (3) and said control chamber (8) by means of a single fitting (13) connected to a supply pipe (14) and coming out inside a supply orifice (15) formed in said body (2) and communicating with said control chamber (8) and with a supply duct for feeding fuel into said injection chamber (3).
Claim 3
Dependent Claim
45 words
2) - An injector as claimed in Claim 1, characterised by the fact that said supply duct is formed substantially inside a number of sleeves (16, 17) housed in an axial hole (19) in said body (2) and inside which said plunger (1) slides axially.
Claim 4
Dependent Claim
75 words
3) - An injector as claimed in Claim 2, characterised by the fact that said body (2) comprises a second axial hole (8) defining said control chamber, said hole (8) being formed in the top of said body (2) and communicating with and being smaller in diameter than said first axial hole (19); said supply orifice (15) terminating in said control chamber having its axis substantially perpendicular to that of said second axial hole (8).
Claim 5
Dependent Claim
134 words
4) - An injector as claimed in claim 1, 2 or 3, characterised by the fact that it comprises a top sleeve (16), an intermediate sleeve (17) and a bottom sleeve (18), said intermediate sleeve (17) housing a spring (31) coaxial with said plunger (1) and designed to secure the same in a position wherein it closes said injection orifices (4); said duct for supplying fuel to said injection chamber (3) comprising an annular cavity (20) formed in said body (2), coaxial with said axial hole (19), and inside which terminates said fuel supply orifice (15); an axial groove (23) formed in said top sleeve (16); a first annular chamber (24) formed between said sleeves (16, 17) and said body (2); and at least a radial hole (25) formed in said intermediate sleeve (17).
Claim 6
Dependent Claim
86 words
5) - An injector as claimed in one of the foregoing Claims from 2 to 4, characterised by the fact that said bottom sleeve (18) is also housed inside a cavity (34) on said injection nozzle (5); said nozzle (5) being positioned angularly in relation to said body (2) by means of a radial pin (32) inserted between said bottom sleeve (18), said body (2) and said nozzle (5); an annular elastic element (35) being provided between said bottom sleeve (18) and said intermediate sleeve (17).
Claim 7
Dependent Claim
130 words
6) - An injector as claimed in one of the foregoing Claims, wherein said electromagnetic metering valve (6) comprises a mobile plugging member (38) for controlling fuel passage through said drain orifice (7) from said control chamber (8) to said low-pressure chamber (11), and which is activated by a disc-shaped anchor (40) attracted by an electromagnet core (41) and loaded by a spring (42) located between said core (41) and said anchor (40) and exerting force on said anchor (40) in the opposite direction to that exerted by said electromagnet; characterised by the fact that it comprises a second helical spring (45) located between said anchor (40) and said body (2), coaxial with said anchor (40), and designed to exert pressure on and guide said anchor (40) during its movement.
Claim 8
Dependent Claim
49 words
7) - An injector as claimed in Claim 6, characterised by the fact that an annular spacer (47) is provided between said anchor (40) and said core (41) for preventing the surface of said anchor (40) facing said core (41) from contactiang the corresponding surface of said core (41).
Claim 9
Dependent Claim
48 words
8) - An injector as claimed in one of the foregoing Claims from 2 to 7, characterised by the fact that said plunger (1) is connected in sliding manner inside said top sleeve (16); a seal (37) being provided between said top sleeve (16) and said body (2).
References Cited (Backward Citations)
No citation records indexed.
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