US5673669A — Hydraulically-actuated fluid injector having pre-…

Claim 1

Independent Claim 125 words

A hydraulically-actuated electronically-controlled unit fuel injector for receiving fuel at a low supply pressure and for injecting fuel into a combustion chamber of an engine during an injection sequence, comprising: a source of high pressure hydraulic actuating fluid; an injector body having an injector orifice; an intensification and pressurization member disposed in the body for pressurizing fuel to a selectable level independent of and substantially higher than the supply pressure when said intensification and pressurization member is in fluid communication with said actuating fluid source; a valve for selectively opening and closing fluid communication between said actuating fluid source and said intensifier piston; and means disposed in the injector body for injecting pressurized fuel through the orifice into the combustion chamber at any selectable time.

Claim 2

Dependent Claim 125 words

A hydraulically-actuated electronically-controlled unit fuel injector for receiving fuel at a low supply pressure and for injecting fuel into a combustion chamber of an engine during an injection sequence, comprising: a source of high pressure hydraulic actuating fluid; an injector body having an injector orifice; an intensification and pressurization member disposed in the body for pressurizing fuel to a selectable level independent of and substantially higher than the supply pressure when said intensification and pressurization member is in fluid communication with said actuating fluid source; a valve for selectively opening and closing fluid communication between said actuating fluid source and said intensifier piston; and means disposed in the injector body for injecting pressurized fuel through the orifice into the combustion chamber at any selectable time.

Claim 3

Dependent Claim 15 words

The fuel injector of claim 1, wherein the intensification and pressurization member includes a plunger.

Claim 4

Dependent Claim 28 words

The fuel injector of claim 2, further including a high pressure storage volume inside the injector body wherein the plunger is movable within the high pressure storage volume.

Claim 5

Dependent Claim 39 words

The fuel injector of claim 3, wherein the plunger is movable toward a travel limit as fuel is being pressurized and wherein the injecting means is actuated to inject fuel as the plunger is moving toward the travel limit.

Claim 6

Dependent Claim 40 words

The fuel injector of claim 3, wherein the plunger is movable toward a travel limit as fuel is being pressurized and wherein the injecting means is actuated to inject fuel when the plunger is disposed substantially at the travel limit.

Claim 7

Dependent Claim 38 words

The fuel injector of claim 1, wherein the injecting means includes a first valve for controlling delivery of fuel to the intensification and pressurization member and a second valve for controlling delivery of pressurized fuel through the orifice.

Claim 8

Dependent Claim 22 words

The fuel injector of claim 6, wherein the injecting means further includes a single actuator for controlling the first and second valves.

Claim 9

Dependent Claim 30 words

The fuel injector of claim 7, wherein the actuator comprises a solenoid having a first armature coupled to the first valve and a second armature coupled to the second valve.

Claim 10

Dependent Claim 24 words

The fuel injector of claim 6, wherein the first valve comprises a pressure control valve and the second valve comprises a three-way poppet valve.

Claim 11

Dependent Claim 37 words

The fuel injector of claim 1, wherein the injecting means comprises a check movable between open and closed positions and means for substantially balancing forces acting on the check in each of the open and closed positions.

Claim 12

Dependent Claim 51 words

The fuel injector of claim 10, further including a high pressure storage volume inside the injector body and wherein the check includes first and second check ends and the balancing means comprises first and second passages extending between the high pressure storage volume and the first and second check ends, respectively.

Claim 13

Dependent Claim 51 words

The fuel injector of claim 11, wherein the injecting means further includes a poppet valve for selectively coupling the first check end to a low pressure source while the second check end is coupled to the high pressure storage volume when the check is to be moved to the open position.

Claim 14

Dependent Claim 63 words

The fuel injector of claim 12, wherein the injecting means further includes a spring which urges the check toward the closed position and wherein the poppet valve fluidly recouples the first end of the check to the high pressure storage volume when the check is to be moved to the closed position and wherein such movement occurs under the influence of the spring.

Claim 15

Dependent Claim 16 words

The fuel injector of claim 13, wherein the poppet valve is selectively controlled by a solenoid.

Claim 16

Dependent Claim 17 words

The fuel injector or claim 14, further comprising: a pressure control valve selectively controlled by the solenoid.

Claim 17

Dependent Claim 25 words

The fuel injector of claim 15, wherein the solenoid includes first and second armatures coupled to the pressure control valve and the poppet valve, respectively.

Claim 18

Dependent Claim 42 words

The fuel injector of claim 16, wherein the armatures are coaxial and spaced from one another with an air gap therebetween and wherein the solenoid includes a winding which, when energized, develops flux that causes the armatures to move toward one another.

Claim 19

Dependent Claim 21 words

The fuel injector of claim 17, wherein the solenoid further includes a spring which urges the armatures away from one another.

Claim 20

Dependent Claim 173 words

A hydraulically-actuated electronically controlled fuel injector for injecting fuel into a combustion chamber of an engine during an injection sequence, comprising: a source of high pressure hydraulic actuating fluid; an injector body having an injector orifice; a reciprocable intensification and pressurization member disposed in said injector body for pressurizing a selected quantity of fuel to a selected pressure, said intensification and pressurization member being driven by said high pressure hydraulic actuating fluid; and means disposed in the injector body for injecting pressurized fuel through the orifice into the combustion chamber at any selectable point in the injection sequence including a check having first and second check ends and movable between an open position at which fuel is injected into the combustion chamber and a closed position at which the flow of pressurized fuel into the combustion chamber is blocked and means for selectively applying either a low fluid pressure or a high fluid pressure directly to each of the first and second ends to move the check between the open and closed positions.

Claim 21

Dependent Claim 173 words

A hydraulically-actuated electronically controlled fuel injector for injecting fuel into a combustion chamber of an engine during an injection sequence, comprising: a source of high pressure hydraulic actuating fluid; an injector body having an injector orifice; a reciprocable intensification and pressurization member disposed in said injector body for pressurizing a selected quantity of fuel to a selected pressure, said intensification and pressurization member being driven by said high pressure hydraulic actuating fluid; and means disposed in the injector body for injecting pressurized fuel through the orifice into the combustion chamber at any selectable point in the injection sequence including a check having first and second check ends and movable between an open position at which fuel is injected into the combustion chamber and a closed position at which the flow of pressurized fuel into the combustion chamber is blocked and means for selectively applying either a low fluid pressure or a high fluid pressure directly to each of the first and second ends to move the check between the open and closed positions.

Claim 22

Dependent Claim 19 words

The fuel injector of claim 19, wherein fuel is supplied to the fuel injector at a low supply pressure.

Claim 23

Dependent Claim 15 words

The fuel injector of claim 19, wherein said intensification and pressurization member includes a plunger.

Claim 24

Dependent Claim 28 words

The fuel injector of claim 21, further including a high pressure storage volume inside the injector body wherein the plunger is movable within the high pressure storage volume.

Claim 25

Dependent Claim 39 words

The fuel injector of claim 12, wherein the plunger is movable toward a travel limit as fuel is being pressurized and wherein the injecting means is actuated to inject fuel as the plunger is moving toward the travel limit.

Claim 26

Dependent Claim 40 words

The fuel injector of claim 22, wherein the plunger is movable toward a travel limit as fuel is being pressurized and wherein the injecting means is actuated to inject fuel when the plunger is disposed substantially at the travel limit.

Claim 27

Dependent Claim 42 words

The fuel injector of claim 20, wherein the injecting means includes a first valve for controlling delivery of fuel to the intensification and pressurization member and the applying means includes a second valve for controlling delivery of pressurized fuel through the orifice.

Claim 28

Dependent Claim 18 words

The fuel injector of claim 25, further including a single actuator for controlling the first and second valves.

Claim 29

Dependent Claim 30 words

The fuel injector of claim 26, wherein the actuator comprises a solenoid having a first armature coupled to the first valve and a second armature coupled to the second valve.

Claim 30

Dependent Claim 24 words

The fuel injector of claim 25, wherein the first valve comprises a pressure control valve and the second valve comprises a three-way poppet valve.

Claim 31

Dependent Claim 42 words

The fuel injector of claim 20, further including a high pressure storage volume inside the injector body and wherein the applying means comprises first and second passages extending between the high pressure storage volume and the first and second check ends, respectively.

Claim 32

Dependent Claim 51 words

The fuel injector of claim 29, wherein the applying means further includes a poppet valve for selectively coupling the first check end to a low pressure source while the second check end is coupled to the high pressure storage volume when the check is to be moved to the open position.

Claim 33

Dependent Claim 62 words

The fuel injector of claim 30, wherein the injecting means further includes a spring which urges the check toward the closed position and wherein the poppet valve couples the first end of the check to the high pressure storage volume when the check is to be moved to the closed position and wherein such movement occurs under the influence of the spring.

Claim 34

Dependent Claim 16 words

The fuel injector of claim 30, wherein the poppet valve is selectively controlled by a solenoid.

Claim 35

Dependent Claim 17 words

The fuel injector of claim 32, further comprising: a pressure control valve selectively controlled by the solenoid.

Claim 36

Dependent Claim 25 words

The fuel injector of claim 33, wherein the solenoid includes first and second armatures coupled to the pressure control valve and the poppet valve, respectively.

Claim 37

Dependent Claim 42 words

The fuel injector of claim 34, wherein the armatures are coaxial and spaced from one another with an air gap therebetween and wherein the solenoid includes a winding which, when energized, develops flux that causes the armatures to move toward one another.

Claim 38

Dependent Claim 21 words

The fuel injector of claim 33, wherein the solenoid further includes a spring which urges the armatures away from one another.

Claim 39

Dependent Claim 94 words

A directly controlled, hydraulically actuated unit injector, comprising: a source of high pressure hydraulic actuating fluid; an intensification and pressurization member for pressurizing fuel to a selectable level when fluidly connected to said source; a first valve for controlling pressurization of fuel; a second valve movable between a first and a second position for controlling injection of pressurized fuel; a single actuator for controlling the first and second valves; and a check movable between an injecting position and a non-injecting position in response to said second valve moving between its first and second positions.

Claim 40

Dependent Claim 94 words

A directly controlled, hydraulically actuated unit injector, comprising: a source of high pressure hydraulic actuating fluid; an intensification and pressurization member for pressurizing fuel to a selectable level when fluidly connected to said source; a first valve for controlling pressurization of fuel; a second valve movable between a first and a second position for controlling injection of pressurized fuel; a single actuator for controlling the first and second valves; and a check movable between an injecting position and a non-injecting position in response to said second valve moving between its first and second positions.

Claim 41

Dependent Claim 30 words

The unit injector of claim 37, wherein the actuator comprises a solenoid having a first armature coupled to the first valve and a second armature coupled to the second valve.

Claim 42

Dependent Claim 42 words

The unit injector of claim 38, wherein the armatures are coaxial and spaced from one another with an air gap therebetween and wherein the solenoid includes a winding which, when energized, develops flux that causes the armatures to move toward one another.

Claim 43

Dependent Claim 21 words

The unit injector of claim 39, wherein the solenoid further includes a spring which urges the armatures away from one another.

Claim 44

Dependent Claim 173 words

The unit injector of claim 39, wherein the air gap is of a first size when the winding is deenergized and further including a high pressure storage volume in fluid communication with the first valve, said check being in fluid communication with the second valve and having first and second check ends of substantially equal effective cross-sectional dimensions and an injection control coupled to the solenoid wherein the injection control energizes the solenoid at the beginning of an injection sequence to move the first and second valves toward each other such that the first valve closes the high pressure storage volume and wherein the injection control then deenergizes the solenoid to cause the second valve to move away from the first valve while the first valve remains stationary such that the air gap is of a second size less than the first size and such that the first and second check ends are coupled to the high pressure storage volume and wherein the injection control may thereafter initiate injection by energizing the solenoid.

Claim 45

Independent Claim 182 words

A method of injecting fuel into a combustion chamber of an internal combustion engine using a fuel injector having an injector body, a check having first and second ends disposed in the injector body and movable between injecting and non-injecting positions, a spring urging the check into the non-injecting position and coupling means for selectively coupling either high or low fluid to the first and second check ends, comprising the steps of: (a.) controlling the coupling means to cause the high fluid pressure to be applied to one end of the check; (b.) thereafter controlling the coupling means to cause the low fluid pressure to be applied to the first check end while the high fluid pressure is being applied to the second check end so that the check is moved to the injecting position against the urging of the spring; and (c.) thereafter controlling the coupling means to cause the high fluid pressure to be applied to the first and second check ends so that the check is moved to the non-injecting position in response to the urging of the spring.

Claim 46

Independent Claim 182 words

A method of injecting fuel into a combustion chamber of an internal combustion engine using a fuel injector having an injector body, a check having first and second ends disposed in the injector body and movable between injecting and non-injecting positions, a spring urging the check into the non-injecting position and coupling means for selectively coupling either high or low fluid to the first and second check ends, comprising the steps of: (a.) controlling the coupling means to cause the high fluid pressure to be applied to one end of the check; (b.) thereafter controlling the coupling means to cause the low fluid pressure to be applied to the first check end while the high fluid pressure is being applied to the second check end so that the check is moved to the injecting position against the urging of the spring; and (c.) thereafter controlling the coupling means to cause the high fluid pressure to be applied to the first and second check ends so that the check is moved to the non-injecting position in response to the urging of the spring.

Claim 47

Dependent Claim 42 words

The method of claim 42, wherein the steps (a.), (b.) and (c.) include the step of operating a solenoid having an armature coupled to a valve wherein the valve selectively couples the check ends and sources of high and low fluid pressures.

Claim 48

Dependent Claim 38 words

The method of claim 42, wherein the step (a.) includes the step of deenergizing a solenoid having an armature coupled to a valve wherein the valve selectively couples the check ends and a source of high fluid pressure.

Claim 49

Dependent Claim 39 words

The method of claim 42, wherein the step (b.) includes the step of energizing a solenoid having an armature coupled to a valve wherein the valve selectively couples the check ends and sources of high and low fluid pressures.

Claim 50

Dependent Claim 38 words

The method of claim 42, wherein the step (c.) includes the step of deenergizing a solenoid having an armature coupled to a valve wherein the valve selectively couples the check ends and a source of high fluid pressure.

Claim 51

Dependent Claim 47 words

The method of claim 42, further including the step of pressurizing fuel provided to the injector at a supply pressure to a pressure level independent of engine speed and supply pressure and wherein the step (b.) includes the step of delivering the pressurized fuel to the check.

Claim 52

Dependent Claim 16 words

The method of claim 42, further including the step of repeating step (b.) after step (c.).

Claim 53

Independent Claim 308 words

A method of injecting fuel into a combustion chamber of an internal combustion engine using a unit injector having an injector body, a high pressure storage volume disposed in the injector body, a plunger reciprocable into the high pressure storage volume and movable to pressurize fuel therein, a source of high pressure actuating fluid, an intensification and pressurization member which drives the plunger to pressurize the fuel when fluidly connected to the high pressure actuating fluid source, a check disposed in the injector body having first and second check ends of substantially equal effective cross-sectional dimensions and movable between injecting and non-injecting positions, a pressure control valve in fluid communication with the high pressure storage volume and a poppet valve in fluid communication between the check ends and the high pressure storage volume and a source of low fluid pressure, comprising the steps of: (a.) fluidly connecting the high pressure actuating fluid source to the intensification and pressurization member; (b.) providing a solenoid in the injector body having a first armature coupled to the pressure control valve, a second armature coupled to the poppet valve and a winding energizable to cause the armatures to be displaced relative to one another; (c.) energizing the winding as the plunger is moving into the high pressure storage volume to cause the pressure control valve to close the high pressure storage volume and pressurize fuel therein; (d.) deenergizing the winding to place the first and second check ends in fluid communication with the high pressure storage volume; and (e.) energizing the winding again to place the first check end in fluid communication with the source of low fluid pressure and the second check end in fluid communication with the high pressure storage volume so that a pressure differential across the check moves the check to the injecting position and initiates fuel injection.

Claim 54

Independent Claim 308 words

A method of injecting fuel into a combustion chamber of an internal combustion engine using a unit injector having an injector body, a high pressure storage volume disposed in the injector body, a plunger reciprocable into the high pressure storage volume and movable to pressurize fuel therein, a source of high pressure actuating fluid, an intensification and pressurization member which drives the plunger to pressurize the fuel when fluidly connected to the high pressure actuating fluid source, a check disposed in the injector body having first and second check ends of substantially equal effective cross-sectional dimensions and movable between injecting and non-injecting positions, a pressure control valve in fluid communication with the high pressure storage volume and a poppet valve in fluid communication between the check ends and the high pressure storage volume and a source of low fluid pressure, comprising the steps of: (a.) fluidly connecting the high pressure actuating fluid source to the intensification and pressurization member; (b.) providing a solenoid in the injector body having a first armature coupled to the pressure control valve, a second armature coupled to the poppet valve and a winding energizable to cause the armatures to be displaced relative to one another; (c.) energizing the winding as the plunger is moving into the high pressure storage volume to cause the pressure control valve to close the high pressure storage volume and pressurize fuel therein; (d.) deenergizing the winding to place the first and second check ends in fluid communication with the high pressure storage volume; and (e.) energizing the winding again to place the first check end in fluid communication with the source of low fluid pressure and the second check end in fluid communication with the high pressure storage volume so that a pressure differential across the check moves the check to the injecting position and initiates fuel injection.

Claim 55

Dependent Claim 53 words

The method of claim 49, wherein a spring is in contact with the check and including the further step of deenergizing the winding again after the step (d.) to remove the pressure differential across the check and cause the check to be moved to the non-injecting position under the influence of the spring.

Claim 56

Dependent Claim 24 words

The method of claim 50, including the further step of reenergizing the winding to move the check to the injecting position a second time.

Claim 57

Dependent Claim 30 words

The method of claim 49, wherein the step (a.) includes the step of providing a spring between the first and second armatures for urging the armatures away from one another.

Claim 58

Dependent Claim 32 words

The method of claim 49, wherein the pressure control valve keeps the high pressure storage volume closed when the fluid pressure in the high pressure storage volume is above a certain level.

Claim 59

Dependent Claim 22 words

The method of claim 50, including the further step of allowing energy to be recovered from the actuating fluid after fuel injection.

Claim 60

Dependent Claim 205 words

A hydraulically actuated, electronically controlled unit fuel injector adapted to receive fuel from a fuel supply at relatively low pressure and inject fuel at relatively high pressure into a combustion chamber of an internal combustion engine over a series of injector cycles comprising: (a) an injector body containing an internal bore and injector valve; (b) a plunger mounted for reciprocating movement at varying velocity within said internal bore; (b') a source of high pressure actuating fluid; (b") an intensification and pressurization member, when fluidly coupled to the high pressure actuating fluid, drives said plunger; (c) a high pressure storage volume into which fuel is received at low pressure from the fuel supply and from which fuel is discharged periodically at relatively high pressure through said injector valve means into the combustion chamber; and (d) injection control means for causing an amount of fuel to be injected at a selected time through the injector valve at a pressure which is independent of: (1) the pressure of fuel received from the fuel supply; (2) changes in the velocity of the reciprocating movement of said plunger; (3) the amount of fuel delivered through the injector valve; and (4) the amount, injection pressure, or timing of previous injection cycles.

Claim 61

Dependent Claim 205 words

A hydraulically actuated, electronically controlled unit fuel injector adapted to receive fuel from a fuel supply at relatively low pressure and inject fuel at relatively high pressure into a combustion chamber of an internal combustion engine over a series of injector cycles comprising: (a) an injector body containing an internal bore and injector valve; (b) a plunger mounted for reciprocating movement at varying velocity within said internal bore; (b') a source of high pressure actuating fluid; (b") an intensification and pressurization member, when fluidly coupled to the high pressure actuating fluid, drives said plunger; (c) a high pressure storage volume into which fuel is received at low pressure from the fuel supply and from which fuel is discharged periodically at relatively high pressure through said injector valve means into the combustion chamber; and (d) injection control means for causing an amount of fuel to be injected at a selected time through the injector valve at a pressure which is independent of: (1) the pressure of fuel received from the fuel supply; (2) changes in the velocity of the reciprocating movement of said plunger; (3) the amount of fuel delivered through the injector valve; and (4) the amount, injection pressure, or timing of previous injection cycles.

Claim 62

Dependent Claim 22 words

The unit fuel injector of claim 55, wherein said fuel pressurization chamber is located between said plunger and said injection control means.

Claim 63

Dependent Claim 101 words

Method for recovering energy from hydraulic actuating fluid expelled from a hydraulically actuated, electronically controlled unit fuel injector following injection of fuel into a combustion chamber, said injector being selectively fluidly coupled to an actuating fluid pump to cause fuel injection, said method comprising: (a) driving an actuating fluid motor coupled to the actuating fluid pump with actuating fluid expelled from the injector; (b) providing fluid communication between the injector and the actuating fluid motor after completion of fuel injection; and (c) obstructing fluid communication between the injector and the actuating fluid motor at a selected time after initiating step (b).

Claim 64

Dependent Claim 101 words

Method for recovering energy from hydraulic actuating fluid expelled from a hydraulically actuated, electronically controlled unit fuel injector following injection of fuel into a combustion chamber, said injector being selectively fluidly coupled to an actuating fluid pump to cause fuel injection, said method comprising: (a) driving an actuating fluid motor coupled to the actuating fluid pump with actuating fluid expelled from the injector; (b) providing fluid communication between the injector and the actuating fluid motor after completion of fuel injection; and (c) obstructing fluid communication between the injector and the actuating fluid motor at a selected time after initiating step (b).

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2000-10-06	2001-04-07	2001-10-07	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2004-10-06	2005-04-07	2005-10-07	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2008-10-06	2009-04-07	2009-10-07	$7700.00	Window Closed / Lapsed

Hydraulically-actuated fluid injector having pre-injection pressurizable fluid storage chamber and direct-operated check

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