Lubrication oil controlled unit injector

A fuel injector for periodic injection of fuel into a combustion chamber of an engine at variable times and in variable amounts from cycle to cycle under the control of the engine lubrication fluid, comprising:

• an injector body containing an injector cavity and an injector orifice communicating with one end of said injector cavity, said injector body including a lubrication fluid timing circuit and a fuel metering circuit fluidically separate from said lubrication fluid timing circuit;
• plunger means mounted for reciprocal movement within said injector cavity, said plunger means including a timing plunger and a metering plunger;
• a timing chamber formed in said injector cavity between said timing plunger and said metering plunger, said timing chamber communicating with said lubrication fluid timing circuit;
• a metering chamber formed in said injector cavity between said metering plunger and said injector orifice;
• an electromagnetic valve means for controlling the timing and metering of fuel injection by the fuel injector on a cycle by cycle basis by controlling the flow of lubrication fluid in said lubrication fluid timing circuit, said electromagnetic valve means positioned within said lubrication fluid timing circuit for controlling the flow of lubrication fluid through said lubrication fluid timing circuit, wherein said electromagnetic valve means is operable to be placed in a first position in which lubrication fluid may flow through said lubrication fluid timing circuit into said timing chamber and fuel flow from said fuel metering circuit into said metering chamber is shut off, and a second position in which lubrication fluid flow into said timing chamber is shut off, wherein movement of said electromagnetic valve means into said first position stops movement of said metering plunger in said injector cavity.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine, comprising:

• an injector body containing an injector cavity and a discharge orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber;
• a timing chamber formed in said injector cavity for receiving timing fluid;
• a tinting fluid supply circuit formed in said injector body for delivering timing fluid to said tinting chamber;
• a metering chamber formed in said injector cavity between said timing chamber and said discharge orifice for receiving metering fuel;
• a metering fuel supply circuit formed in said injector body for delivering metering fuel to said metering chamber;
• a control valve means for controlling the flow of timing fluid in said timing fluid supply circuit, wherein the timing fluid in said timing fluid supply circuit upstream of said control valve is constantly maintained at a pressure greater than the pressure of the metering fuel in said metering fuel supply circuit, wherein said timing fluid supply circuit is separate from said metering fuel supply circuit, said control valve means operable to vary the amount of fuel into said metering chamber for subsequent fuel injection by the fuel injector on a cycle by cycle basis.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine at variable times from cycle to cycle under the control of the engine lubrication fluid, comprising:

• an injector body containing an injector cavity and a discharge orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber, said injector body including a lubrication fluid timing circuit and a fuel metering circuit separate from said lubrication fluid timing circuit;
• and
• a variable hydraulic timing and metering means for varying the timing and metering of fuel injection by the fuel injector on a cycle by cycle basis by controlling the flow of lubrication fluid in said lubrication fluid timing circuit to form a lubrication fluid link having a variable effective length positioned in said lubrication fluid timing circuit within said injector cavity, said variable hydraulic timing and metering means including a control valve positioned within said lubrication fluid timing circuit for controlling the flow of lubrication fluid in said lubrication fluid timing circuit to vary said variable effective length of said lubrication fluid link to vary the timing of fuel injection, said control valve operable to vary the metering of fuel for fuel injection by the fuel injector on a cycle by cycle basis, further including a timing plunger and a metering plunger reciprocally mounted in said injector cavity, a timing chamber formed in said injector cavity between said timing plunger and said metering plunger for receiving said lubrication fluid link and a metering chamber formed in said injector cavity between said metering plunger and said discharge orifice, said control valve including an electromagnetic valve operable to be placed in a first position in which lubrication fluid may flow through said lubrication fluid timing circuit into said timing chamber to vary said variable effective length of said lubrication fluid link and fuel flow from said fuel metering circuit into said metering chamber is stopped, and a second position in which lubrication fluid flow into said timing chamber is shut off to define a specific effective length of said lubrication fluid link, wherein movement of said electromagnetic valve into said first position stops movement of said metering plunger in said injector cavity.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine at variable times from cycle to cycle under the control of the engine lubrication fluid, comprising:

• an injector body containing an injector cavity and a discharge orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber, said injector body including a lubrication fluid timing circuit and a fuel metering circuit separate from said lubrication fluid timing circuit;
• and
• a variable hydraulic timing and metering means for varying the timing and metering of fuel injection by the fuel injector on a cycle by cycle basis by controlling the flow of lubrication fluid in said lubrication fluid timing circuit to form a lubrication fluid link having a variable effective length positioned in said lubrication fluid timing circuit within said injector cavity, said variable hydraulic timing and metering means including a control valve positioned within said lubrication fluid timing circuit for controlling the flow of lubrication fluid in said lubrication fluid timing circuit to vary said variable effective length of said lubrication fluid link to vary the timing of fuel injection, said control valve operable to vary the metering of fuel for fuel injection by the fuel injector on a cycle by cycle basis, further including a timing plunger and a metering plunger reciprocally mounted in said injector cavity, a timing chamber formed in said injector cavity between said timing plunger and said metering plunger for receiving said lubrication fluid link, a metering chamber formed in said injector cavity between said metering plunger and said discharge orifice, a linking means for transmitting a driving force to said timing plunger, said linking means engaging one end of said timing plunger, and an annular clearance gap formed between said timing plunger and said injector cavity for permitting lubrication fluid to flow from said timing chamber through said clearance gap to said linking means to lubricate said linking means.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine at variable times and in variable amounts from cycle to cycle under the control of the engine lubrication fluid, comprising:

• an injector body containing an injector cavity and an injector orifice communicating with one end of said injector cavity, said injector body including a lubrication fluid timing circuit and a fuel metering circuit fluidically separate from said lubrication fluid timing circuit;
• plunger means mounted for reciprocal movement within said injector cavity, said plunger means including a timing plunger and a metering plunger;
• a timing chamber formed in said injector cavity between said timing plunger and said metering plunger, said timing chamber communicating with said lubrication fluid timing circuit;
• a metering chamber formed in said injector cavity between said metering plunger and said injector orifice;
• a linking means for transmitting a driving force to said timing plunger, said linking means engaging one end of said timing plunger, and an annular clearance gap formed between said timing plunger and said injector cavity for permitting lubrication fluid to flow from said timing chamber through said clearance gap to said linking means to lubricate and cool said linking means;
• and
• an electromagnetic valve means for controlling the timing and metering of fuel injection by the fuel injector on a cycle by cycle basis by controlling the flow of lubrication fluid in said lubrication fluid timing circuit, said electromagnetic valve means positioned within said lubrication fluid timing circuit for controlling the flow of lubrication fluid through said lubrication fluid timing circuit, wherein said electromagnetic valve means is operable to be placed in a first position in which lubrication fluid may flow through said lubrication fluid timing circuit into said timing chamber and fuel flow from said fuel metering circuit into said metering chamber is shut off, and a second position in which lubrication fluid flow into said timing chamber is shut off.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine, comprising:

• an injector body containing an injector cavity and a discharge orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber;
• a timing chamber formed in said injector cavity for receiving timing fluid;
• a timing fluid supply circuit formed in said injector body for delivering timing fluid to said timing chamber;
• a metering chamber formed in said injector cavity between said timing chamber and said discharge orifice for receiving metering fuel;
• a metering fuel supply circuit formed in said injector body for delivering metering fuel to said metering chamber;
• a control valve means for controlling the flow of timing fluid in said timing fluid supply circuit, wherein the timing fluid in said timing fluid supply circuit upstream of said control valve is constantly maintained at a pressure greater than the pressure of the metering fuel in said metering fuel supply circuit;
• and
• a timing fluid spill valve means for permitting the flow of timing fluid from said injector cavity for return to said timing fluid supply circuit, said timing fluid spill valve means including a timing fluid spill port formed in said injector body and communicating with said timing chamber and a first raised section formed on said metering plunger adjacent said timing fluid spill port and movable into a blocking position in which timing fluid flow through said timing fluid spill port is shut off and a spill position which permits timing fluid flow through said timing fluid spill port.

A fuel injector for periodic injection of fuel into a combustion chamber of an engine at variable times from cycle to cycle under the control of the engine lubrication fluid, comprising:

• an injector body containing an injector cavity and a discharge orifice communicating with one end of said injector cavity to discharge fuel into the combustion chamber, said injector body including a lubrication fluid timing circuit and a fuel metering circuit separate from said lubrication fluid timing circuit;
• a variable hydraulic timing and metering means for varying the timing and metering of fuel injection by the fuel injector on a cycle by cycle basis by controlling the flow of lubrication fluid in said lubrication fluid timing circuit to form a lubrication fluid link having a variable effective length positioned in said lubrication fluid timing circuit within said injector cavity, said variable hydraulic timing and metering means including a control valve positioned within said lubrication fluid timing circuit for controlling the flow of lubrication fluid in said lubrication fluid timing circuit to vary said variable effective length of said lubrication fluid link to vary the timing of fuel injection, said control valve operable to vary the metering of fuel for fuel injection by the fuel injector on a cycle by cycle basis;
• and
• a timing plunger and a metering plunger reciprocally mounted in said injector cavity, a tinting chamber formed in said injector cavity between said timing plunger and said metering plunger for receiving said lubrication fluid link and a metering chamber formed in said injector cavity between said metering plunger and said discharge orifice, wherein said lubrication fluid timing circuit is separate from said fuel metering circuit, said control valve operable to vary the amount of fuel into said metering chamber for subsequent fuel injection by the fuel injector on a cycle by cycle basis.