|Publication number||US6925989 B2|
|Application number||US 10/643,046|
|Publication date||Aug 9, 2005|
|Filing date||Aug 18, 2003|
|Priority date||Aug 18, 2003|
|Also published as||DE102004039338A1, US20050039725|
|Publication number||10643046, 643046, US 6925989 B2, US 6925989B2, US-B2-6925989, US6925989 B2, US6925989B2|
|Inventors||Christopher John Treusch, Joe Zhi Li, Robert Eugene Wattleworth|
|Original Assignee||Visteon Global Technologies, Inc.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (44), Referenced by (19), Classifications (9), Legal Events (12)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of Invention
The present invention relates generally to fuel pressure pulsation damping systems, and more particularly to a fuel pressure pulsation damping system with reduced pulsation magnitudes at resonate modes of the fuel deliver system.
2. Description of the Known Technology
Conventional methods of damping pressure pulsations in a fuel system rely solely on inclusion of a member that introduces more compliance (a “compliance member”), thereby reducing the bulk modulus of the system. This can be accomplished through the use of a conventional fuel pressure damper, an internal damper or inherent/self-damping, the latter being where a member of the fuel delivery system in fluid communication with the pulsating fuel is provided with a flexible wall or walls to absorb the pressure fluctuations within the system. The location of these compliance members generally are governed solely by manufacturing and packaging concerns.
Simply adding compliance is not always sufficient to relieve all of the objectionable pressure pulsations in the fuel delivery system however. It can also result in unwanted variation in the fuel injector performance as well as objectionable noise, vibration and harshness. In some systems where adding sufficient compliance is possible, it may not be commercially feasible or physically practical to introduce a custom designed compliant damping system. The additional compliance may make certain members too weak to function properly or require expensive materials to achieve the desired effect.
Resolving these resonant frequency issues simply by adding more compliance can result in other unwanted effects. Adding more compliance may allow more pulsations to be absorbed, but it will also result in a shift in frequency of resonant modes of the system. As compliance is increased, the frequency of resonant modes of the system shift to lower frequencies. When the frequency of the modes shift lower, higher resonant modes that were previously above the operating frequency range of the fuel system (and thus previously not a problem) may shift into the operating frequency range of the fuel system. Therefore, adding more compliance can sometimes result in more objectionable resonant frequency modes than before.
It remains desirable to provide a means of damping objectionable pressure pulsations to thereby limit the maximum operating system pulse magnitude, other than by merely adding compliance.
The present invention overcomes the disadvantages of the known technology by including one or more restrictors within identified critical elements of a fuel rail to increase the damping ratio of the resonant mode, and thereby achieve the desired damping of pressure fluctuations. A problem arises when the operating frequency excites one of various resonant modes of the system. From this resonant mode, it can be determined which elements of the fuel delivery system contribute most to the resonant mode. Such an element can be a distinct component of the fuel delivery system, such as a jumper tube between two sides of a fuel rail assembly or it can be a significant structure for resonant modes within a component, such as a long straight section of pipe between two injector ports, integrated into a larger component of the fuel rail. At the frequencies where some of these resonant modes are excited, the maximum operating system pulse magnitude can increase to several times normal operating levels. Such resonant modes and the associated system elements are herein referred to as the critical modes and critical elements.
According to the present invention, a restrictor is located within, or in proximity to, an identified critical element or elements that would otherwise contribute significantly to critical resonant modes, which cause pressure pulsations above a specified level within the operating frequency range of the system. These restrictors serve to increase the damping ratio of the critical modes, and thereby dampen the system sufficiently to reduce maximum operating pulse magnitudes below a specified level required in the given application.
It is an object and advantage that the present invention results in avoiding objectionable pressure fluctuations in a fuel system.
It is an additional object and advantage that the present invention results in limiting maximum operating system pulse magnitudes, without introducing additional resonant modes into the operating frequency range of the fuel system.
These and other advantages, features and objects of the invention will become apparent from the drawings, detailed description and claims, which follow.
Referring now to the drawings,
At particular rpm and loads within the operating range of the vehicle and fuel system, the pressure spikes and the fuel pressure can reach magnitudes in excess of ten times that experienced during other periods of operation. These large pressure magnitudes in turn can create objectionable noise, vibration and harshness in the fuel system or exceed the specified maximum pressure pulse magnitude. Engineers thus need to develop systems that must operate in specific operational ranges with a design that avoids major pressure pulses in the system. These large magnitude pressure spikes are dependent on and differ based on specific designs.
Often, dampers 10 will be added to dampen out the objectionable pulsations. The addition or modification of a damper 10 can alter the resonant modes of the system 8 however, sometimes moving a resonant mode that previously existed beyond the operating frequency range into the operating frequency range. Engineers can find themselves iteratively changing dampers 10 in an attempt to find the best compromise.
Pressure fluctuations in the fuel are put into the system 8 by the fuel pump, pressure release caused by firing injectors on the output side, and the interaction of these inputs and outputs among the elements of the fuel system 8. In a conventional system 8, the damper 10 is in fluid communication with the fluid passage 20 to absorb fuel pressure pulsations. In some systems, this damper can be as elementary as a thin wall in one of the fuel system components that flexes in response to pressure increases. In more complicated systems discrete dampers, such as the one illustrated, include a flexible diaphragm 30 is supported by a spring or other means 40 to absorb pulsation energy in the fluid passage 20. Still further examples of damping systems include providing an internal damper in the fuel rail and providing the fuel rail/system with inherent or self-damping via the incorporation of flexible wall elements in the system.
As mentioned above, dampers are often developed and positioned in an iterative process with little regard to the interaction of the various components in how they function to reduce pressure fluctuations. Often more compliance elements are introduced in conventional systems to absorb energy and thus reduce the pulsations and their undesirable effects. However, such more compliance in the system can create other problems as mentioned above. The present invention overcomes such problems.
When a fuel system is swept or run through the rpm range over which it will be expected to operate, pressure spikes of magnitudes beyond acceptable design specifications can be identified. By conducting an FFT analysis on a given pressure spike, a frequency can be determined that primarily contributes to that spike. This is herein referred to as the “critical frequency”. From the critical frequency, the resonant mode associated with the pressure spike can be identified. This is referred to herein as the “critical mode”. Often more than one pressure spike in the rpm sweep is due to a single critical mode. Using a shape modal analysis, an element(s) of the fuel system that contributes most to the critical mode can be identified. This element(s) is referred to herein as the “critical element(s)”.
The inventors have discovered that identifying the critical element and locating a restrictor in the critical element will substantially increase the damping ratio of the critical mode, resulting in a maximum reduction in the pressure spike(s) associated therewith. The inventors have further discovered that the restrictor may even be located outside of the critical element, in the proximity of the critical element, resulting in an acceptable reduction in the magnitude of the pressure spike, to levels of acceptability for the given design and application.
Referring now to
As mentioned above, one or more critical elements 134 can be defined within the system 100. It should be noted that the critical element(s) 134 may be a discrete part of the fuel system 100, such as the cross-over rail 126, or it may be a portion of the system 100, such as a section of one of the side rails 122, 124 between two or tire fuel injectors 128.
Two critical members 134, 136 are shown, for illustrative purposes, in the system 100. The first critical member 134 is identified as the cross-over rail 126, while the second critical member 136 is identified as a section of the first side rail 122 between two of the fuel injectors 128.
A restrictor 138 is located in relation to the critical element 134, 136 in order to reduce the maximum operating pulse magnitude contributed by that critical element 134, 136. It should be pointed out that all systems contain inherent compliance as a result of component material, component design and configuration. Some designs incorporate the damping function into the fuel rail wall design. This built-in compliance can sometimes meet all of the required compliance needed by the system. In these cases, there may not be a discrete damper, as other system components provide this function. By locating the restrictor 138 in the correct relation to an identified critical element 134, 136, one can increase the damping ratio and thereby reduce the maximum operating system pulse magnitude, without introducing new and unwanted other resonant modes.
Optimum restrictor location may not always be possible or practical because of packaging or other constraints. Locating a restrictor in a less than optimum position may sail serve to adequately reduce the maximum operating system pulse magnitude below that specified by design criteria. In such instances, locating the restrictor in proximity to the critical element may achieve sufficient benefits in terms of magnitude reduction so as to reduce the magnitude of the pressure spike to within acceptable design criteria. This is seen with regard to the critical element 136 and the location of a restrictor 142 in proximity to the critical element 136 itself. In such instance only a percentage of the optimal benefit, the benefit gained by placing the restrictor within the critical element, will be achieved.
The effectiveness of the restrictor can be represented by a linear function of the distance from the optimum location to the restrictor. In general, the efficiency of a restrictor location compared to an optimally placed one can be generally represented by the equation E=1.000−0.00226×D, where E is the efficiency and D is the distance from the end of the critical element (in millimeters). Represented in another way, D=(1.00−E)/0.00226.
With the restrictor located in proximity to the critical element, the maximum operating pulse magnitude caused by the particular critical element is lowered. The effect that the restrictor has on reducing the maximum operating pulse magnitude may lower the magnitude of the operating pulse to within the requirements of the specified maximum operating pulse magnitude for a system. In such a case, optimum placement of the restrictor is not a requirement, and the restrictor may be positioned some distance from the end point of the critical element. Rewriting the efficiency term E of the prior equation, the allowable distance that a restrictor can be moved from the end point of a critical element can be substantially expressed by the equation D=(1.000−[Rr/Ra]/0.00226, where Rr is the required effect on the maximum pulse magnitude and Ra is the actual effect on pulse magnitude caused by the restrictor. Thus, if an optimum restrictor (located within (zero millimeters from) the critical element) reduces the actual maximum operating system pulse magnitude, Ra, by a factor of 4, and the specified or required maximum operating system pulse magnitude, Rr, is twice as large, the system can afford a 50% efficiency in the placement of the restrictor. From the graph and table of
While the above first order equations yields very good results in predicting percent of optimum benefit gained, an inspection of the graph in
Referring now to
While the invention has been described with regard to fuel systems, it is anticipated that the invention will have applicability to hydraulic systems in general where pressure pulsations need to be reduced.
The foregoing discussion discloses and describes a preferred embodiment of the invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that changes and modifications can be made to the invention without departing from the true spirit and fair scope of the invention as defined in the following claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1426009||Aug 8, 1921||Aug 15, 1922||Edward J Rantsch||Axle mounting for motor vehicles|
|US1507012||Apr 8, 1922||Sep 2, 1924||Weier John J||Vehicle driving and steering mechanism|
|US1861640||Jul 8, 1927||Jun 7, 1932||Apex Electrical Mfg Co||Washing machine|
|US2015430||Mar 2, 1935||Sep 24, 1935||Int Motor Co||Involute spline shaft|
|US2259460||Apr 17, 1939||Oct 21, 1941||Reynolds B Dexter||Resilient drive bushing|
|US2969250||Jan 5, 1959||Jan 24, 1961||Standard Pressed Steel Co||Socket drive|
|US3665967||Jan 16, 1970||May 30, 1972||Western Co Of North America||Supercharge hose|
|US4056679||Sep 27, 1976||Nov 1, 1977||I-T-E Imperial Corporation||Sodium filled flexible transmission cable|
|US4210372||Jun 19, 1978||Jul 1, 1980||Caterpillar Tractor Co.||Retainer for bearing lock nut|
|US4651781||Aug 2, 1985||Mar 24, 1987||Northrop Corporation||Distributed accumulator|
|US4660524 *||Mar 15, 1985||Apr 28, 1987||Robert Bosch Gmbh||Fuel supply line|
|US4838832||Oct 22, 1987||Jun 13, 1989||Manfred Schmitt||Tooth system for a shaft-hub connection|
|US4897906||Apr 24, 1989||Feb 6, 1990||Proprietary Technology, Inc.||Method of making a fluid pressure surge damper for a fluid system|
|US4924584||Jul 12, 1988||May 15, 1990||Magna International Inc.||Method of fastening a tubular element to a member and joint produced thereby|
|US5056489 *||Jul 10, 1989||Oct 15, 1991||Siemens-Bendix Automotive Electronics L.P.||Fuel rail for v-type engine|
|US5197436 *||Dec 20, 1991||Mar 30, 1993||Yamaha Hatsudoki Kabushiki Kaisha||Fuel delivery system for V-type engine|
|US5213437||Dec 5, 1989||May 25, 1993||Zahnradfabrik Friedrichshafen, Ag||Serrated-shaft connection|
|US5373824 *||Aug 6, 1993||Dec 20, 1994||Ford Motor Company||Acoustical damping device for gaseous fueled automotive engines|
|US5575262||Nov 16, 1994||Nov 19, 1996||Robert Bosch Gmbh||Damper element for damping compressive oscillations and method for producing the same|
|US5664655||Oct 14, 1994||Sep 9, 1997||Samsung Heavy Industry Co., Ltd.||Spline|
|US5674026||Feb 21, 1995||Oct 7, 1997||Unisia Jecs Corporation||Shaft coupling structure of drive shaft|
|US5697850||Mar 13, 1995||Dec 16, 1997||Matsui Universal Joint Manufacturing Company||Driving shaft having splined male and female portions|
|US5709248||Sep 30, 1996||Jan 20, 1998||Caterpillar Inc.||Internal accumulator for hydraulic systems|
|US5752486 *||Dec 18, 1996||May 19, 1998||Nippon Soken Inc.||Accumulator fuel injection device|
|US5884607 *||Oct 21, 1997||Mar 23, 1999||Robert Bosch Gmbh||Fuel delivery system for a vehicle|
|US6101907||Nov 25, 1998||Aug 15, 2000||Snap-On Tools Company||Interference fit joint and method and indexable ratchet wrench utilizing same|
|US6314942||Apr 25, 2000||Nov 13, 2001||Siemens Automotive Corporation||Fuel pressure dampening element|
|US6354273 *||Feb 17, 2000||Mar 12, 2002||Usui Kokusai Sangyo Kaisha Ltd.||Fuel delivery rail assembly|
|US6390131||Sep 15, 2000||May 21, 2002||Siemens Automotive Corporation||Retaining clip and assembly for internal dampening element|
|US6418910 *||Oct 5, 2001||Jul 16, 2002||Siemens Automotive Corporation||Rail geometry for minimization of fluid pressure pulsations|
|US6615801 *||May 2, 2002||Sep 9, 2003||Millennium Industries Corp.||Fuel rail pulse damper|
|US6640783 *||Dec 21, 2001||Nov 4, 2003||Delphi Technologies, Inc.||Composite fuel rail with integral damping and a co-injected non-permeation layer|
|US6725839 *||May 29, 2002||Apr 27, 2004||Millennium Industries Corp.||Stamped metal fuel rail|
|US20020043249||Oct 10, 2001||Apr 18, 2002||Ki-Ho Lee||Fuel rail with intergal dampening features|
|US20020053341||Jan 9, 2002||May 9, 2002||Izumi Imura||Fuel delivery rail assembly|
|EP0780569A1||Dec 18, 1996||Jun 25, 1997||Nippon Soken, Inc.||Accumulator fuel injection device|
|EP0785357A1||Jan 14, 1997||Jul 23, 1997||Toyota Jidosha Kabushiki Kaisha||Fuel delivery apparatus in V-type engine|
|EP1162364A1||Jun 7, 2001||Dec 12, 2001||Toyota Jidosha Kabushiki Kaisha||Fuel injection apparatus|
|EP1188919A2||Mar 15, 2001||Mar 20, 2002||Hitachi, Ltd.||Fuel supply system|
|EP1199466A2||Oct 11, 2001||Apr 24, 2002||Siemens Automotive Inc.||Fuel rail with integral dampening features|
|JP2001099031A||Title not available|
|JP2001107821A||Title not available|
|JP2001207931A||Title not available|
|JP2001280217A||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7146965 *||May 31, 2005||Dec 12, 2006||Automotive Components Holdings, Llc||Enhanced fuel pressure pulsation damping system with low flow restriction|
|US7406946||Apr 2, 2007||Aug 5, 2008||Hitachi, Ltd.||Method and apparatus for attenuating fuel pump noise in a direct injection internal combustion chamber|
|US7527038||Jul 2, 2008||May 5, 2009||Hitachi, Ltd||Method and apparatus for attenuating fuel pump noise in a direct injection internal combustion chamber|
|US7690356 *||Feb 27, 2009||Apr 6, 2010||Honda Motor Co., Ltd.||Internal combustion engine|
|US7827962 *||Nov 30, 2006||Nov 9, 2010||Robert Bosch Gmbh||High-pressure accumulator body with integrated distributor block|
|US7942132||Jul 8, 2009||May 17, 2011||Robert Bosch Gmbh||In-line noise filtering device for fuel system|
|US8037868||Apr 11, 2011||Oct 18, 2011||Robert Bosch Gmbh||In-line noise filtering device for fuel system|
|US8161945||Sep 12, 2011||Apr 24, 2012||Robert Bosch Gmbh||In-line noise filtering device for fuel system|
|US8251047||Aug 27, 2010||Aug 28, 2012||Robert Bosch Gmbh||Fuel rail for attenuating radiated noise|
|US8402947||Jun 22, 2012||Mar 26, 2013||Robert Bosch Gmbh||Fuel rail for attenuating radiated noise|
|US20060266333 *||May 31, 2005||Nov 30, 2006||Visteon Global Technologies, Inc.||Enhanced fuel pressure pulsation damping system with low flow restriction|
|US20070163546 *||Dec 14, 2006||Jul 19, 2007||Toyota Jidosha Kabushiki Kaisha||Vibration-reducing structure for fuel pipe|
|US20090223486 *||Nov 30, 2006||Sep 10, 2009||Christoph Weizenauer||High-Pressure Accumulator Body With Integrated Distributor Block|
|US20090241902 *||Feb 27, 2009||Oct 1, 2009||Honda Motor Co., Ltd.||Internal combustion engine|
|US20100012091 *||Jan 21, 2010||Robert Bosch Gmbh||In-line noise filtering device for fuel system|
|US20110192378 *||Aug 11, 2011||Robert Bosch Gmbh||In-line noise filtering device for fuel system|
|USRE43864||Aug 4, 2010||Dec 18, 2012||Hitachi, Ltd.||Method and apparatus for attenuating fuel pump noise in a direct injection internal combustion chamber|
|CN101438052B||Nov 30, 2006||Jun 6, 2012||罗伯特·博世有限公司||High-pressure accumulator body with integrated distributor block|
|CN101755118B||Jun 10, 2008||Oct 3, 2012||罗伯特.博世有限公司||Internal combustion engine having a plurality of cylinders|
|U.S. Classification||123/456, 138/30, 123/468, 123/467|
|International Classification||F02M69/46, F02M63/00|
|Cooperative Classification||F02M69/465, F02M2200/315|
|Jan 7, 2004||AS||Assignment|
Owner name: VISTEON GLOBAL TECHNOLOGIES, INC., MICHIGAN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:TREUSCH, CHRISTOPHER JOHN;LI, JOE ZHI;WATTLEWORTH, ROBERT EUGENE;REEL/FRAME:014855/0939;SIGNING DATES FROM 20031211 TO 20031215
|Dec 1, 2005||AS||Assignment|
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|Feb 15, 2006||AS||Assignment|
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