US5687693A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulically-actuated fuel injector with direct control needle valve
Assignee: Caterpillar Inc
•
Filing: 1996-08-30
•
Granted: 1997-11-18
•
Expires: 2016-08-30
Abstract
Abstract A hydraulically actuated fuel injector includes an injector body having an actuation fluid inlet, an actuation fluid cavity, a nozzle chamber open to a nozzle outlet and a needle control chamber. A hydraulic means within the injector pressurizes fuel in the nozzle chamber. The hydraulic means includes an actuation fluid control valve having a solenoid and is moveable between a first position in which the actuation fluid inlet is open to the actuation fluid cavity and a second position in which the actuation fluid inlet is closed to the actuation fluid cavity. A needle valve member is positioned to reciprocate in the nozzle chamber between an open position in which the nozzle outlet is open and a closed position in which the nozzle outlet is closed. The needle valve member includes a closing hydraulic surface exposed to pressure in the needle control chamber. A needle control valve that also utilizes the same solenoid is attached to the injector body and moveable between an off position in which the needle control chamber is opened to a source of high pressure fluid and an on position in which the needle control chamber is opened to a low pressure passage. The slower response time of the actuation fluid control valve allows for direct control of the fast responding needle valve.
Inventors
- 👤 Shikui K. Chen
- 👤 Gregory W. Hefler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:07
CPC Classifications
F; F02; F02G; F02G5/00; F02M; F02M45/00; F02M45/02; F02M45/04; F02M47/00; F02M47/02; F02M47/027; F02M47/04; F02M47/043; F02M57/00; F02M57/02; F02M57/022; F02M57/025; F02M59/00; F02M59/02; F02M59/10; F02M59/105; F02M59/20; F02M59/36; F02M59/366; F02M59/44; F02M59/46; F02M59/466; F02M63/00; F02M63/0012; F02M63/0014; F02M63/0015; F02M63/0017; F02M63/0028; F02M63/0029; F02M63/0031; F02M63/004; F02M63/0042; F02M63/0045; F02M63/0049; F02M63/0059; F02M63/0061; F02B; F02B2275/00; F02B2275/14; F02M2200/00; F02M2200/21; F02M2200/50; F02M2200/502; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
197 words
A hydraulically actuated fuel injector comprising: an injector body having an actuation fluid inlet, an actuation fluid cavity, a nozzle chamber open to a nozzle outlet, and a needle control chamber; hydraulic means, within said injector body, for pressurizing fuel in said nozzle chamber, said hydraulic means including an actuation fluid control valve having a solenoid and being movable between a first position in which said actuation fluid inlet is open to said actuation fluid cavity and a second position in which said actuation fluid inlet is closed to said actuation fluid cavity; a needle valve member positioned to reciprocate in said nozzle chamber between an open position in which said nozzle outlet is open and a closed position in which said nozzle outlet is closed, and said needle valve member including a closing hydraulic surface exposed to pressure in said needle control chamber; a needle control valve having said solenoid and being attached to said injector body and being movable between an off position in which said needle control chamber is opened to a source of high pressure fluid and an on position in which said needle control chamber is opened to a low pressure passage.
Claim 2
Dependent Claim
197 words
A hydraulically actuated fuel injector comprising: an injector body having an actuation fluid inlet, an actuation fluid cavity, a nozzle chamber open to a nozzle outlet, and a needle control chamber; hydraulic means, within said injector body, for pressurizing fuel in said nozzle chamber, said hydraulic means including an actuation fluid control valve having a solenoid and being movable between a first position in which said actuation fluid inlet is open to said actuation fluid cavity and a second position in which said actuation fluid inlet is closed to said actuation fluid cavity; a needle valve member positioned to reciprocate in said nozzle chamber between an open position in which said nozzle outlet is open and a closed position in which said nozzle outlet is closed, and said needle valve member including a closing hydraulic surface exposed to pressure in said needle control chamber; a needle control valve having said solenoid and being attached to said injector body and being movable between an off position in which said needle control chamber is opened to a source of high pressure fluid and an on position in which said needle control chamber is opened to a low pressure passage.
Claim 3
Dependent Claim
36 words
The fuel injector of claim 1, wherein said source of high pressure fluid is said actuation fluid inlet; said injector body includes an actuation fluid drain; and said low pressure passage is said actuation fluid drain.
Claim 4
Dependent Claim
65 words
The fuel injector of claim 2, wherein said injector body includes an actuation fluid control passage that extends between said needle control chamber and said needle control valve; and said needle control valve including a low pressure seat separating said actuation fluid drain and said actuation fluid control passage and a high pressure seat separating said actuation fluid inlet and said actuation fluid control passage.
Claim 5
Dependent Claim
35 words
The fuel injector of claim 3 wherein said needle control valve further includes a pin attached to said solenoid, and a ball valve member positioned between said low pressure seat and said high pressure seat.
Claim 6
Dependent Claim
92 words
The fuel injector of claim 2 wherein said hydraulic means for pressurizing includes: said injector body having a plunger bore, a piston bore and an actuation fluid cavity that opens to said actuation fluid inlet; an intensifier piston positioned to reciprocate in said piston bore between a forward position and a return position; a plunger positioned to reciprocate in said plunger bore between a retracted position and an advanced position; and a portion of said plunger bore and said plunger define a fuel pressurization chamber that is open to said nozzle chamber.
Claim 7
Dependent Claim
49 words
The fuel injector of claim 5 wherein said actuation fluid control valve further includes: a pin attached to said solenoid; said injector body having a low pressure seat and a high pressure seat; and a ball valve member positioned between said low pressure seat and said high pressure seat.
Claim 8
Dependent Claim
107 words
The fuel injector of claim 6 wherein said actuation fluid control valve further includes a spool valve member movable between a first position and a second position; said spool valve member opens said actuation fluid cavity to said actuation fluid inlet and closes said actuation fluid drain to said actuation fluid cavity when in said first position; said spool valve member closes said actuation fluid cavity to said actuation fluid inlet and opens said actuation fluid drain to said actuation fluid cavity when in said second position; and means, including a spring positioned in said injector body, for biasing said spool valve member toward said second position.
Claim 9
Dependent Claim
61 words
The fuel injector of claim 7 wherein said spool valve member has an end hydraulic surface exposed to pressure in actuation fluid control passage; and said spool valve member being hydraulically biased toward said first position when said ball valve member is seated in said high pressure seat and said actuation fluid control passage is open to said actuation fluid drain.
Claim 10
Dependent Claim
34 words
The fuel injector of claim 5 wherein said piston bore is a stepped bore; and said intensifier piston has a stepped top that is received in said stepped bore when in said return position.
Claim 11
Dependent Claim
63 words
The fuel injector of claim 1 wherein said needle valve member includes an opening hydraulic surface exposed to pressure in said nozzle chamber; said closing hydraulic surface and said opening hydraulic surface are sized and arranged such that said needle valve member is hydraulically biased toward said closed position when said needle control chamber is opened to said source of high pressure fluid.
Claim 12
Dependent Claim
87 words
The fuel injector of claim 9 further comprising a spring in contact with said needle valve member, for biasing said needle valve member toward said closed position when pressure in said nozzle chamber is below a valve opening pressure and said needle control chamber is opened to said low pressure passage; and said needle valve member is biased toward said opened position when said needle control chamber is connected to said low pressure passage and pressure in said nozzle chamber is greater than said valve opening pressure.
Claim 13
Dependent Claim
23 words
The fuel injector of claim 2 wherein said needle valve member includes a spring mounted between a needle portion and an intensifier portion.
Claim 14
Dependent Claim
155 words
A fuel injection system comprising: a plurality of hydraulically actuated fuel injectors with direct control needle valves, each injector having hydraulic means for pressurizing fuel that includes a an actuation fluid control valve with a solenoid, a needle valve member with a closing hydraulic surface exposed to pressure in a needle control chamber and a needle control valve with said solenoid that alternately opens said needle control chamber to a source of high pressure fluid or a low pressure passage, and each injector also having an actuation fluid inlet, an actuation fluid drain and a fuel supply passage; a source of fuel connected to said fuel supply passage of each said injector; a source of high pressure actuation fluid connected to said actuation fluid inlet; a low pressure reservoir connected to said actuation fluid drain; and a computer in communication with and capable of controlling said needle control valve and said actuation fluid control valve.
Claim 15
Dependent Claim
155 words
A fuel injection system comprising: a plurality of hydraulically actuated fuel injectors with direct control needle valves, each injector having hydraulic means for pressurizing fuel that includes a an actuation fluid control valve with a solenoid, a needle valve member with a closing hydraulic surface exposed to pressure in a needle control chamber and a needle control valve with said solenoid that alternately opens said needle control chamber to a source of high pressure fluid or a low pressure passage, and each injector also having an actuation fluid inlet, an actuation fluid drain and a fuel supply passage; a source of fuel connected to said fuel supply passage of each said injector; a source of high pressure actuation fluid connected to said actuation fluid inlet; a low pressure reservoir connected to said actuation fluid drain; and a computer in communication with and capable of controlling said needle control valve and said actuation fluid control valve.
Claim 16
Dependent Claim
148 words
The fuel injection system of claim 13, wherein each said injector body further having an actuation fluid cavity, a nozzle chamber and a nozzle outlet that opens to said nozzle chamber; said actuation fluid control valve being movable between a first position in which said actuation fluid inlet is open to said actuation fluid cavity and a second position in which said actuation fluid inlet is closed to said actuation fluid cavity; said needle valve member being positioned to reciprocate in said nozzle chamber between an opened position in which said nozzle outlet is open and a closed position in which said nozzle outlet is closed; said needle control valve being movable between an off position in which said needle control chamber is opened to said source of high pressure fluid and an on position in which said needle control chamber is opened to said low pressure passage.
Claim 17
Dependent Claim
48 words
The fuel injection system of claim 14 wherein each said injector has only one two-way solenoid; said needle control valve is movable between said off position and said on position substantially faster than said actuation fluid control valve can move from said first position to said second position.
Claim 18
Dependent Claim
187 words
The fuel injection system of claim 15 wherein said needle control valve includes a pin attached to said solenoid, said injector body having a low pressure seat between an actuation fluid drain and said actuation fluid control passage, said injector body having a high pressure seat between said actuation fluid inlet and said actuation fluid control passage and a ball valve member positioned between said low pressure seat and said high pressure seat; said actuation fluid control valve includes said pin, said low pressure seat, said high pressure seat, said ball valve member, a spool valve member movable between a first position and a second position and means, including a spring positioned in said injector body, for biasing said spool valve member toward said second position; said spool valve member opens said actuation fluid cavity to said actuation fluid inlet and closes said actuation fluid drain to said actuation fluid cavity when in said first position; and said spool valve member closes said actuation fluid cavity to said actuation fluid inlet and opens said actuation fluid drain to said actuation fluid cavity when in said second position.
Claim 19
Independent Claim
151 words
A method of fuel injection comprising the steps of: providing a hydraulically actuated fuel injector having a nozzle chamber open to a nozzle outlet, a needle valve member and a single two-way solenoid that is part of a needle control valve and an actuation fluid control valve, and said needle control valve having an off position and an on position, and said actuation fluid control valve having an open position and a closed position; energizing said solenoid for an amount of time sufficient to move said actuation fluid control valve from said closed position to said open position and move said needle control valve from said off position to said on position; hydraulically pressurizing fuel in said nozzle chamber to an injection pressure; moving said needle valve member to open said nozzle outlet; and de-energizing said solenoid to move said needle control valve from said on position to said off position.
Claim 20
Independent Claim
151 words
A method of fuel injection comprising the steps of: providing a hydraulically actuated fuel injector having a nozzle chamber open to a nozzle outlet, a needle valve member and a single two-way solenoid that is part of a needle control valve and an actuation fluid control valve, and said needle control valve having an off position and an on position, and said actuation fluid control valve having an open position and a closed position; energizing said solenoid for an amount of time sufficient to move said actuation fluid control valve from said closed position to said open position and move said needle control valve from said off position to said on position; hydraulically pressurizing fuel in said nozzle chamber to an injection pressure; moving said needle valve member to open said nozzle outlet; and de-energizing said solenoid to move said needle control valve from said on position to said off position.
Claim 21
Dependent Claim
97 words
The method of claim 17 wherein the method further comprising the step of de-energizing said solenoid, before said step of moving said needle valve member, for a sufficient amount of time to move said needle control valve from said on position to said off position but an insufficient amount of time for said actuation fluid control valve to move from said open position to said closed position; and said step of moving said needle valve member includes a step of re-energizing said solenoid to move said needle control valve from said off position to said on position.
Claim 22
Dependent Claim
42 words
The method of claim 18 further comprising the step of moving said needle valve member to open said nozzle outlet for a pilot injection; and re-energizing said solenoid to move said needle control valve from said off position to said on position.
Claim 23
Dependent Claim
35 words
The method of claim 18 wherein said step of de-energizing said solenoid, before said step of moving said needle valve member, is performed before fuel in said injector is pressurized above a valve opening pressure.
References Cited (Backward Citations)
US33270A
Cited
US3175771A
Cited
US3241768A
Cited
US3361161A
Cited
US3450353A
Cited
US3443760A
Cited
US3592568A
Cited
US3570806A
Cited
US3570807A
Cited
US3532121A
Cited
US3570833A
Cited
US3661130A
Cited
US3742918A
Cited
US3604959A
Cited
US3743898A
Cited
US3683239A
Cited
US3821967A
Cited
US3989066A
Cited
US4040569A
Cited
US4120456A
Cited
US4064855A
Cited
US4107546A
Cited
US4108419A
Cited
US4114647A
Cited
US4192466A
Cited
US4269360A
Cited
US4096995A
Cited
US4129255A
Cited
US4258674A
Cited
US4671232A
Cited
US4714066A
Cited
US4343280A
Cited
US4417557A
Cited
US4409638A
Cited
US4541454A
Cited
US4392612A
Cited
US4516600A
Cited
USRE33270E
Cited
US4628881A
Cited
US4501290A
Cited
US4561701A
Cited
US4580598A
Cited
US4498625A
Cited
US4544096A
Cited
US4603671A
Cited
US4482094A
Cited
US4568021A
Cited
US4635854A
Cited
US4586656A
Cited
US4838232A
Cited
US4721253A
Cited
US4681080A
Cited
US4709679A
Cited
US4618095A
Cited
US4831989A
Cited
US4777921A
Cited
US5201295A
Cited
US4782807A
Cited
US4811221A
Cited
US4813601A
Cited
US4840160A
Cited
US4870940A
Cited
US4934599A
Cited
US4946103A
Cited
US5072882A
Cited
US4964571A
Cited
US4951631A
Cited
US4951874A
Cited
US4993637A
Cited
US4969600A
Cited
US5082180A
Cited
US5007584A
Cited
US5109822A
Cited
US5033442A
Cited
US4957085A
Cited
US5046472A
Cited
US5353991A
Cited
US5141164A
Cited
US5295469A
Cited
US5133645A
Cited
US5230613A
Cited
US5094215A
Cited
US5155461A
Cited
US5180138A
Cited
US5161775A
Cited
US5221046A
Cited
US5121730A
Cited
US5265804A
Cited
US5143291A
Cited
US5235954A
Cited
US5370095A
Cited
US5271598A
Cited
US5271563A
Cited
US5347970A
Cited
US5335852A
Cited
US5441028A
Cited
US5325834A
Cited
US5441029A
Cited
US5497750A
Cited
US5585547A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-11-17 | 2001-05-19 | 2001-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-11-17 | 2005-05-19 | 2005-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-11-17 | 2009-05-19 | 2009-11-18 | $7700.00 | Window Closed / Lapsed |