Internal-combustion engines – Charge forming device – Fuel injection system
Reexamination Certificate
2000-10-23
2002-10-22
Moulis, Thomas N. (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel injection system
C123S467000
Reexamination Certificate
active
06467457
ABSTRACT:
TECHNICAL FIELD
The present invention relates generally to hydraulically actuated fuel injection systems. More particularly, the present invention relates to devices for minimizing pressure fluctuations in the actuating fluid system.
BACKGROUND OF THE INVENTION
Hydraulically actuated, electronically controlled unit injection systems (HEUI) injectors require a source of high pressure actuating fluid. Each of the fuel injectors of an engine is typically serviced by a common high pressure actuating fluid rail. The rail usually runs along the head of a bank of cylinders. In the past, tubular connectors have extended between the rail and individual injectors for conveying high pressure actuating fluid to the injector. It is important for both engine performance and engine noise emission considerations that each injector have a stable source of high pressure actuating fluid.
Each HEUI injector has an internal actuator that turns on and off the high pressure actuating fluid to the injector. The cycling of the actuator, at least once every injection event, may cause a water hammer effect that is transmitted through the connector to the rail. The water hammer effect causes pressure instability in the rail and is also a source of objectionable engine noise emission. In the prior art, for V-form engines, a check valve or check valves have been interposed in the plumbing that connects the two high pressure rails serving each bank of cylinders. Such a design is the subject of U.S. Pat. No. 5,168,855 to Stone and an exemplary schematic of this design is presented in prior art FIG.
9
. The prior art actuating fluid system
400
includes a high pressure pump
402
that draws actuating fluid from a low pressure reservoir
404
. A rail pressure control valve
406
monitors (via sensor communication
407
) and controls the maximum pressure in the rails by dumping pressure back to the reservoir
404
via fluid ling
408
under certain conditions. The design of the prior art system
400
is for a V form engine of six cylinders (and, in fact, is inapplicable to an engine with a single bank of cylinders serviced by a single rail). Accordingly, a check valve
410
is disposed in the fluid line to the left rail
412
and a check valve is disposed in the fluid line to the right rail
414
. Each of the rails
412
,
414
supplies high pressure actuating fluid directly to the three injectors
416
,
418
on the bank of cylinders served by the respective rail
412
,
414
. A pressure fluctuation emanating from an injector
416
is isolated for the right rail
414
and the injectors
418
serviced by the right rail by the check valves
410
. A pressure fluctuation emanating from a certain injector
416
is translated to the left rail
412
and may affect the operation of the other two injectors
416
. The check valves
410
provide no isolation in the last mentioned case. This last mentioned case is analogous to an inline engine having a single bank of cylinders.
While the mechanization of the '855 patent may partially alleviate cross talk between the two high pressure actuating fluid rails of a V-type engine, the mechanization does nothing to deal with the instabilities induced in a single rail by all of the injectors serviced by that rail. Accordingly, there is a need in the industry to minimize the pressure pulses reaching a high pressure actuating fluid rail from a specific injector. Such means of control should act to stabilize the pressure in the affected high pressure actuating fluid rail as well as minimizing emission noise emanating from the rail due to the presence of the water hammer effect caused by the individual injectors.
Additionally, as indicated above, the mechanization of the ′855 patent simply does not address the problem of an inline engine with a single high pressure actuating fluid rail. All of the injectors serviced by such a rail, typically six or more, are free to send pressure waves through the high pressure actuating rail. Accordingly, there is a further need in the industry for a means to correct the aforementioned problem as it exists in inline engines as well as the problem existing in V-type engines.
SUMMARY OF THE INVENTION
The connector assembly of the present invention substantially meets the aforementioned needs of the industry. Each injector serviced by a high pressure actuating fluid rail is in fluid communication with the rail by means of a connector assembly of the present invention. Each connector assembly of the present invention includes a check valve that is seated by the pressure of the water hammer effect caused by the closing of the injector actuator. Such closing substantially prevents transmission of the water hammer effect to the rail. By containing the water hammer effect, the noise emitted from the rail is substantially reduced. Further, pressure of the high pressure actuating fluid in the rail is substantially stabilized, thereby improving the performance of each of the injectors serviced by the rail.
A further benefit of the connector assembly of the present invention is that it can be utilized to control injector inlet volume and pressure. Such control is beneficial in minimizing the quantity of fuel injected during the pilot injection portion of an injection event. Such control acts to minimize noise emissions from the engine and to improve drivability.
The present invention is a connector assembly and the actuating system including the connector assembly, the connector assembly for fluidly coupling an actuating fluid rail to a fuel injector, the actuating fluid rail conveying a quantity of actuating fluid, the fuel injector having an actuating fluid inlet, the connector assembly includes a check valve operably disposed in a connecting member for controlling the flow of actuating fluid between the actuating fluid rail and the fuel injector. The connecting member has a fluid passageway defined therein, the fluid passageway being in fluid communication with the actuating fluid rail and the fuel injector actuating fluid inlet. The present invention is further a method of minimizing negative pressure effects caused by operation of a fuel injector on the actuating fluid in an actuating fluid rail and a method of providing a high pressure actuating fluid flow from a high pressure pump to a plurality of fuel injectors of a diesel engine.
REFERENCES:
patent: 3742926 (1973-07-01), Kemp
patent: 4286563 (1981-09-01), Magdi et al.
patent: 4295452 (1981-10-01), Lembke et al.
patent: 4577606 (1986-03-01), Bohringer et al.
patent: 4628957 (1986-12-01), Hofer
patent: 4751904 (1988-06-01), Hudson
patent: 4776615 (1988-10-01), Young
patent: 4964391 (1990-10-01), Hoover
patent: 4996961 (1991-03-01), Usui
patent: 4996962 (1991-03-01), Usui
patent: 5058554 (1991-10-01), Takeda et al.
patent: 5143039 (1992-09-01), Gmelin
patent: 5168855 (1992-12-01), Stone
patent: 5211149 (1993-05-01), DeGrace, Jr.
patent: 5273015 (1993-12-01), Yonekawa et al.
patent: 5297523 (1994-03-01), Hafner et al.
patent: 5299542 (1994-04-01), Hafner
patent: 5372113 (1994-12-01), Smith
patent: 5423303 (1995-06-01), Bennett
patent: 5509391 (1996-04-01), Degroot
patent: 5511528 (1996-04-01), Iwanaga et al.
patent: 5517972 (1996-05-01), Stockner
patent: 5531202 (1996-07-01), Lorraine
patent: 5603302 (1997-02-01), Minagawa et al.
patent: 5806494 (1998-09-01), Glassey
patent: 5832954 (1998-11-01), Shafer
patent: 5842452 (1998-12-01), Pattanaik
patent: 5950669 (1999-09-01), Fehlmann et al.
patent: 5954032 (1999-09-01), Augustin et al.
patent: 19606946 (1997-09-01), None
patent: 19734669 (1998-09-01), None
patent: 19735665 (1999-01-01), None
patent: 0829640 (1998-03-01), None
patent: 2021720 (1979-12-01), None
Lei Ning
Seymour, II Kenneth R.
Yager James H.
Yang Xilin
Zielke Martin R.
Calfa Jeffrey P.
International Engine Intellectual Property Company, L.L.C.
Moulis Thomas N.
Powell Neil T.
Sullivan Dennis Kelly
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