# US 5,699,963 A · Electromagnetic valve and unit-type fuel injection device using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,699,963 A - Document ID: US5699963A - Status: Granted - Kind: A - Application number: 08/494,266 - Filed: 1995-06-23 - Granted: 1997-12-23 - Earliest claimed: 1994-07-06 - Assignees: Zexel Corporation - Inventors: Atsushi Ueda - Web page: https://patentgrep.com/patent/US5699963A ## CPC - F02M 57/02: Injectors structurally combined with fuel-injection pumps - F02M 59/366: {Valves being actuated electrically} - F02M 59/466: {Electrically operated valves, e.g. using electromagnetic or piezoelectric operating means} - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF ## Abstract An unit-type fuel injection device including a plunger for pressurizing fuel in a fuel pressurizing chamber, an injection nozzle which has a fuel reservoir and serves to inject the fuel pressurized in the fuel pressurizing chamber, and an electromagnetic valve which has a valve plug and serves to intercept fuel supply to the fuel pressurizing chamber, wherein the valve plug of the electromagnetic valve is provided with an intercommunication hole through which the fuel pressurizing chamber and the fuel reservoir of the injection nozzle intercommunicate with each other when the valve plug intercepts the fuel supply to the fuel pressurizing chamber. ## Claims ### Claim 1 An electromagnetic valve including: a fluid reservoir through which a fluid supply hole and a fluid return hole intercommunicate with each other; and a valve plug which is provided in said fluid reservoir and serves to block intercommunication between said fluid reservoir and a first chamber, wherein said valve plug is provided with an intercommunication hole therein through which said first chamber and a second chamber intercommunicate with each other when said valve plug blocks the intercommunication between said fluid reservoir and said first chamber. ### Claim 2 An electromagnetic valve including: an accommodating hole which houses at least a portion of said electromagnetic valve; a fluid reservoir through which a fluid supply hole and a fluid return hole intercommunicate with each other; and a valve plug which is disposed in said fluid reservoir and serves to block intercommunication between said fluid reservoir and a first chamber, wherein said valve plug is provided with an intercommunication hole therein through which said first chamber and a second chamber intercommunicate with each other when said valve plug blocks the intercommunication between said fluid reservoir and said first chamber, and further wherein said fluid reservoir and said accommodating hole are positioned relative to each other such that at least one coil of said electromagnetic valve is kept substantially free of fuel. ### Claim 3 (depends on 1, 2) The electromagnetic valve as claimed in claim 1 or 2, wherein said first chamber comprises a fuel pressurizing chamber and said second chamber comprises a high-pressure passage which is linked to a nozzle unit for fuel injection. ### Claim 4 (depends on 3) The electromagnetic valve as claimed in claim 3, wherein said intercommunication hole is formed so as to be penetrated through said valve plug while the axial line thereof is coincident with the axial line of said valve plug. ### Claim 5 (depends on 1, 2) The electromagnetic valve as claimed in claim 1 or 2, wherein said intercommunication hole is formed so as to be penetrated through said valve plug while the axial line thereof is coincident with the axial line of said valve plug. ### Claim 6 (depends on 1) An electromagnetic valve as claimed in claim 1, wherein said valve plug is disposed in direct contact with said fluid reservoir. ### Claim 7 (depends on 2) An electromagnetic valve as claimed in claim 2, wherein said fluid reservoir and said accommodating hole are spaced vertically from each other. ### Claim 8 (depends on 2) An electromagnetic valve as claimed in claim 2, wherein said valve plug is disposed in direct contact with said fluid reservoir. ### Claim 9 An unit-type fuel injection device having a fuel pressurizing chamber, including: a plunger which pressurizes fuel in said fuel pressurizing chamber; an injection nozzle which has a fuel reservoir and serves to inject the fuel pressurized in said fuel pressurizing chamber; and an electromagnetic valve which has a valve plug and serves to block fuel supply to said fuel pressurizing chamber, wherein said valve plug of said electromagnetic valve is disposed in said fuel reservoir, and is provided with an intercommunication hole therein through which said fuel pressurizing chamber and said fuel reservoir of said injection nozzle intercommunicate with each other when said valve plug blocks the fuel supply to said fuel pressurizing chamber. ### Claim 10 (depends on 9) The unit-type fuel injection device as claimed in claim 9, wherein said plunger, said injection nozzle and said electromagnetic valve are arranged along the same axial line. ### Claim 11 (depends on 9) An unit-type fuel injection device as claimed in claim 9, wherein said valve plug is disposed in direct contact with said fluid reservoir. ### Claim 12 An electromagnetic valve including: a fluid reservoir which intercommunicates with at least one fuel supply and return hole; a first fuel chamber for pressurizing fuel; and a second fuel chamber for discharging the pressurized fuel; and a valve plug which is disposed in said fluid reservoir at one end portion thereof so as to be movable upwardly and downwardly and selectively allows said fluid reservoir and said first fuel chamber to intercommunicate with each other in accordance with the upward and downward movement thereof, wherein said valve plug has therein an intercommunication hole through which said first fuel chamber and said second fuel chamber intercommunicate with each other when the intercommunication between said fluid reservoir and said first fuel chamber is blocked by said upwardly and downwardly movably valve plug, and said intercommunication hole, said fluid reservoir and said second fuel chamber intercommunicate with one another at said one end portion of said valve plug. ### Claim 13 (depends on 12) The electromagnetic valve as claimed in claim 12, wherein said valve plug has a rod shape. ### Claim 14 (depends on 12) The electromagnetic valve as claimed in claim 12, wherein said valve plug is disposed to be surrounded by coils of said electromagnetic valve. ### Claim 15 (depends on 12) An electromagnetic valve as claimed in claim 12, wherein said valve plug is disposed in direct contact with said fluid reservoir.