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US6079641A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel injector with rate shaping control through piezoelectric nozzle lift

Assignee: Caterpillar Inc
•
Filing: 1998-10-13
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Granted: 2000-06-27
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Expires: 2018-10-13
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Abstract

Abstract A fuel injector includes an injector body that defines a nozzle outlet. A needle valve member is mounted in the injector body and moveable a lift distance between an open position in which the nozzle outlet is open, and a closed position in which the nozzle outlet is blocked. A piezoelectric actuator is mounted in the injector body and is moveable a piezo distance between an off position and an on position. A coupling linkage interconnects the needle valve member to the piezoelectric actuator such that a movement of the piezoelectric actuator is multiplied into a larger movement of the needle valve member.

Inventors

  • 👤 Ronald D. Shinogle
  • 👤 Senthilkumar Rajagopalan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 10:14
CPC Classifications
F; F02; F02M; F02M47/00; F02M47/02; F02M47/027; F02M45/00; F02M45/02; F02M45/04; F02M45/08; F02M45/12; F02M63/00; F02M63/0012; F02M63/0014; F02M63/0015; F02M63/0026; F02M63/0031; F02M63/0043; F02M63/0059; F02M63/0068

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 137 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member mounted in said injector body and being movable a lift distance between an open position in which said nozzle outlet is open, and a closed position in which said nozzle outlet is blocked; a piezoelectric actuator mounted in said injector body and being movable a piezo distance between an off position and an on position; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member; said needle valve member being stoppable at a plurality of different partially open positions between said open position and said closed position; and said coupling linkage including said needle valve member having a closing hydraulic surface.
Claim 2
Dependent Claim 137 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member mounted in said injector body and being movable a lift distance between an open position in which said nozzle outlet is open, and a closed position in which said nozzle outlet is blocked; a piezoelectric actuator mounted in said injector body and being movable a piezo distance between an off position and an on position; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member; said needle valve member being stoppable at a plurality of different partially open positions between said open position and said closed position; and said coupling linkage including said needle valve member having a closing hydraulic surface.
Claim 3
Dependent Claim 33 words
The fuel injector of claim 1 wherein said coupling linkage includes said injector body defining a needle control chamber; and said closing hydraulic surface exposed to fluid pressure in said needle control chamber.
Claim 4
Dependent Claim 48 words
The fuel injector of claim 1 further including a control valve member attached to said piezoelectric actuator and located adjacent a control valve seat defined by said injector body; and a flow area past said control valve seat being a function of a positioning of said piezoelectric actuator.
Claim 5
Dependent Claim 53 words
The fuel injector of claim 1 wherein said injector body defines a nozzle supply passage and a needle control chamber; and said needle valve member includes said closing hydraulic surface exposed to fluid pressure in said needle control chamber, and an opening hydraulic surface exposed to fluid pressure in said nozzle supply passage.
Claim 6
Dependent Claim 18 words
The fuel injector of claim 1 wherein said lift distance is many times greater than said piezo distance.
Claim 7
Dependent Claim 34 words
The fuel injector of claim 1 wherein said needle valve member is held in said closed position at least in part by said coupling linkage when said piezoelectric actuator is in said off position.
Claim 8
Dependent Claim 39 words
The fuel injector of claim 1 wherein said needle valve member includes an outer opening hydraulic surface and an inner opening hydraulic surface that are exposed to different fluid pressures depending upon a positioning of said needle valve member.
Claim 9
Dependent Claim 47 words
The fuel injector of claim 1 wherein said injector body defines a needle control chamber; said closing hydraulic surface exposed to fluid pressure in said needle control chamber; and said fluid pressure in said needle control chamber being a function of a positioning of said piezoelectric actuator.
Claim 10
Dependent Claim 98 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member movably mounted in said injector body; a piezoelectric actuator movably mounted in said injector body; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member; a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator; and said coupling linkage including said needle valve member having a closing hydraulic surface.
Claim 11
Dependent Claim 98 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member movably mounted in said injector body; a piezoelectric actuator movably mounted in said injector body; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member; a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator; and said coupling linkage including said needle valve member having a closing hydraulic surface.
Claim 12
Dependent Claim 30 words
The fuel injector of claim 9 wherein said needle valve member is stoppable at a plurality of different partially open positions between a closed position and a fully open position.
Claim 13
Dependent Claim 36 words
The fuel injector of claim 10 wherein said needle valve member is moveable a lift distance; said piezoelectric actuator is moveable a piezo distance; and said lift distance is many times greater than said piezo distance.
Claim 14
Dependent Claim 39 words
The fuel injector of claim 11 wherein said needle valve member includes an outer opening hydraulic surface and an inner opening hydraulic surface that are exposed to different fluid pressures depending upon a positioning of said needle valve member.
Claim 15
Dependent Claim 34 words
The fuel injector of claim 12 wherein said needle valve member is held in said closed position at least in part by said coupling linkage when said piezoelectric actuator is in said off position.
Claim 16
Dependent Claim 33 words
The fuel injector of claim 13 wherein said coupling linkage includes said injector body defining a needle control chamber; and said closing hydraulic surface exposed to fluid pressure in said needle control chamber.
Claim 17
Dependent Claim 56 words
The fuel injector of claim 14 further including a control valve member attached to said piezoelectric actuator and located in an outlet control passage that opens into said needle control chamber; and a control flow area from said needle control chamber into said outlet control passage being a function of a positioning of said piezoelectric actuator.
Claim 18
Dependent Claim 44 words
The fuel injector of claim 15 wherein said injector body defines a nozzle supply passage connected to said needle control chamber through a branch passage; and said needle valve member includes an opening hydraulic surface exposed to fluid pressure in said nozzle supply passage.
Claim 19
Dependent Claim 117 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member movably mounted in said injector body; a piezoelectric actuator movably mounted in said injector body; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member, and said coupling linkage including said injector body defining a needle control chamber; and said needle valve member including a closing hydraulic surface exposed to fluid pressure in said needle control chamber; and a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator.
Claim 20
Dependent Claim 117 words
A fuel injector including: an injector body defining a nozzle outlet; a needle valve member movably mounted in said injector body; a piezoelectric actuator movably mounted in said injector body; a coupling linkage interconnecting said needle valve member to said piezoelectric actuator, and said coupling linkage multiplying movement of said piezoelectric actuator into a larger movement of said needle valve member, and said coupling linkage including said injector body defining a needle control chamber; and said needle valve member including a closing hydraulic surface exposed to fluid pressure in said needle control chamber; and a flow area past said needle valve member to said nozzle outlet being a function of a voltage applied to said piezoelectric actuator.
Claim 21
Dependent Claim 39 words
The fuel injector of claim 17 wherein said needle valve member includes an outer opening hydraulic surface and an inner opening hydraulic surface that are exposed to different fluid pressures depending upon a positioning of said needle valve member.
Claim 22
Dependent Claim 56 words
The fuel injector of claim 18 further including a control valve member attached to said piezoelectric actuator and located in an outlet control passage that opens into said needle control chamber; and a control flow area from said needle control chamber into said outlet control passage being a function of a positioning of said piezoelectric actuator.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-06-27 2003-12-27 2004-06-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-06-27 2007-12-27 2008-06-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-06-27 2011-12-27 2012-06-27 $7700.00 Window Closed / Lapsed

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