CN1087702A - 柴油内燃机中的燃料喷射过程 - Google Patents

柴油内燃机中的燃料喷射过程 Download PDF

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CN1087702A
CN1087702A CN93116413A CN93116413A CN1087702A CN 1087702 A CN1087702 A CN 1087702A CN 93116413 A CN93116413 A CN 93116413A CN 93116413 A CN93116413 A CN 93116413A CN 1087702 A CN1087702 A CN 1087702A
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nozzle
nozzles
opened
fuel
injection
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CN1050878C (zh
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M·舒兹
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Winterthur Gas and Diesel AG
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Xinsu She Diesel Engine Co ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02BINTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B23/00Other engines characterised by special shape or construction of combustion chambers to improve operation
    • F02B23/02Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
    • F02B23/06Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
    • F02B23/0645Details related to the fuel injector or the fuel spray
    • F02B23/0663Details related to the fuel injector or the fuel spray having multiple injectors per combustion chamber
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M41/00Fuel-injection apparatus with two or more injectors fed from a common pressure-source sequentially by means of a distributor
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02DCONTROLLING COMBUSTION ENGINES
    • F02D41/00Electrical control of supply of combustible mixture or its constituents
    • F02D41/30Controlling fuel injection
    • F02D41/3094Controlling fuel injection the fuel injection being effected by at least two different injectors, e.g. one in the intake manifold and one in the cylinder
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M45/00Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship
    • F02M45/02Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts
    • F02M45/04Fuel-injection apparatus characterised by having a cyclic delivery of specific time/pressure or time/quantity relationship with each cyclic delivery being separated into two or more parts with a small initial part, e.g. initial part for partial load and initial and main part for full load
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/18Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
    • F02M61/1806Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for characterised by the arrangement of discharge orifices, e.g. orientation or size
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02MSUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/02Fuel-injection apparatus having several injectors fed by a common pumping element, or having several pumping elements feeding a common injector; Fuel-injection apparatus having provisions for cutting-out pumps, pumping elements, or injectors; Fuel-injection apparatus having provisions for variably interconnecting pumping elements and injectors alternatively
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02BINTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B3/00Engines characterised by air compression and subsequent fuel addition
    • F02B3/06Engines characterised by air compression and subsequent fuel addition with compression ignition
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/10Internal combustion engine [ICE] based vehicles
    • Y02T10/12Improving ICE efficiencies

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fuel-Injection Apparatus (AREA)

Abstract

本发明的喷射过程,借助于至少两个这样配置于 燃烧室(43)中的喷嘴(1,11)将供给着火冲程中的总燃 料量喷射,使正在分别离开各喷嘴的燃料喷注并不相 互干扰。喷射是以这样方式形成的,首先,第一喷嘴 (1),在气缸(44)中被导向的工作活塞(45)的上止点附 近开启,而第二喷嘴在第一喷嘴仍然开启着的稍后时 间里开启。

Description

本发明涉及一种将燃料喷入柴油型往复式内燃机气缸中的燃烧室内的燃料喷射过程。其中供着火冲程用的总燃料量是由这样配置于燃烧室内的至少两个喷咀喷射的,使离开每一喷咀的燃料喷注并不影响离开另外喷咀的燃料喷注。本发明也涉及完成该过程的装置。
在这种常规的喷射过程中,每一着火冲程所需的燃料量是通过一些同时开启的喷咀输入到燃烧室内的,这些喷咀在工作活塞达到上止点(OTP)后的很短时间内开启,并在上止点后大约曲轴转角20°处再关闭。在该过程中,在气缸内便形成压力分布,在图3中,它以实线PZA代表,其特点是在上止点后很短时间内,该压力在短暂时间内是不变的或稍微平稳地下降,然后在被点燃烧料的作用下再较陡地上升直至达到某一最大值。这种压力分布是不理想的,因为由内燃机结构形成的最大可能的气缸压力未被最佳利用。压力的急增也是不希望的,因为引起内燃机结构应力。在上止点附近的最大压力恒定的压力分布是理想的。
本发明的一个目的是要创造一种柴油内燃机燃料喷射过程,借助于它,使上止点附近的气缸压力分布尽可能接近等压分布。
按照本发明,可以达到这一目的,其中,着火冲程所需总燃料量的喷射是这样进行的,首先,第一喷咀在与气缸配合的工作活塞上止点附近开启,而后第二喷咀开启,此时第一喷咀仍然开启着。
由于总燃料量的错开喷射,可避免图3中所示的公知过程的气缸压力“下垂”,这是通过在上止点之前的短暂时间内借助于第一喷咀的较早的燃料喷射量达到压力逐渐增加来避免的。结果,达到了比以前更好地利用最大可能的气缸压力。发动机的结构应力由于压力逐渐增加也得到改善。
实现本发明这一过程的特别简单的结构的特点是,采用具有由关闭弹簧保持关闭的针阀的喷咀,其中关闭弹簧具有不同的尺寸和/或被施加预应力。
借助于附图,下面详细说明本发明的示例性实施例。
图1简略表示用于实现本发明的这一过程的一种简化的喷咀结构;
图2表示自燃料室看的喷咀结构视图;
图3表示一条说明压力分布和针阀随曲轴转角α而变的曲线。
在图1中表示了一种多缸低速二冲程往复内燃机的一个气缸44,该气缸未被进一步详细表示,它按柴油机过程运转,工作活塞45安装在气缸内,因此能上、下移动。工作活塞45和安装在其上方的气缸盖一起限定了燃烧室43,流体燃料,即柴油由第一喷咀1和第二喷咀11以下面还要详细叙述的方式喷入燃烧室内。在气缸盖46的中央配置一排气阀(未示),因此,在工作活塞45向上移动开始时,形成直流帚气。
公知结构的第一喷咀1本身包括一针阀7,在关阀弹簧8的作用下,它被强制顶靠在喷咀壳体内的阀座1′上。在图1中,在喷咀壳体内的阀座下方设有一盲孔,自盲孔处制出一些通入燃烧室43的喷孔。在图1中,在喷咀壳体内的阀座上方设有压力腔10,它经压力管9连于喷射泵40,燃料自油箱(未示)经输油管41被输送到喷射泵。在喷咀1喷油期间,经输油管9供给压力室10的燃油压力是这样的大,以致能克服弹簧8的关闭压力而使针阀7自阀座1′上升起,从而燃料经喷孔2喷入燃烧室43。管42连于喷咀1的壳体上,它用于输送泄漏的燃油。
第二喷咀11具有跟喷咀1同样的结构,其唯一区别在于作用在针阀17上的关闭弹簧18的直径较关闭弹簧8的直径大。因此,经由管9分支的喷咀11的管19供给的燃油压力必须大于针阀7的开启压力,这样,针阀17才能开启。也可以使关闭弹簧18具有跟弹簧8相同的尺寸,此时调正弹簧18,使其预应力较大。
如图2所示,两喷咀1和11彼此沿直径方向配置在气缸盖46 内,实际上喷孔2和12允许燃料以相反方向的喷注喷出(箭头A和A′)。这是因为在工作活塞45向上移动期间在燃烧室43内产生了一股燃烧空气涡流(箭头B),并且因为离开喷孔2和12的燃料喷注基本上具有相同的方向。相邻喷咀的燃料喷注不能穿透燃烧室43区域的事实是和离开喷咀的燃料喷注相关联的,对喷咀的布置是至关紧要的。
正如已提到的,在图3中的实线PZA表示当总燃料量由每缸几个喷咀同时开启喷射时的气缸压力分布。相比之下,虚线PZ44表示利用本发明规定的用二个错开开启的喷咀喷射的在气缸44中的压力分布。图3还表示了喷咀端部的燃油压力分布,实线PDA代表公知喷射,虚线PD1,11代表为本发明规定的喷射。最后,在图3中还表示了针阀升程,相应于公知喷射过程的喷咀针阀升程以实线HA表示,相应于本发明规定的喷射过程的错开开启的喷咀1、11的针阀升程以虚线H1和H11表示。
具有所述装置的本发明的喷射过程是按下列方式进行的:在排气阀关闭后,借助于工作活塞45的向上冲程,空气在燃烧室43内被压缩,其时气缸44中的压力上升(曲线PZ44)。当工作活塞45的向上冲程接近结束,燃油泵40压力侧的压力也上升,并经管9和19分配给喷咀1和11。在泵压大约300巴的时候,克服第一喷咀1中的弹簧8的关闭压力,从而在上止点前大约曲线转角2°处喷咀1的针阀7开启,开始喷射柴油(点X1)。通过燃烧室43内这些燃油的着火和燃烧,气缸44中的压力平缓上升(曲线PZ44),此时,第二喷咀11仍然保持关闭状态。在曲轴转角8°的喷油延续时间间隔内,由燃油泵40产生的压力被分散了,因此不超过第二喷咀11的开启压力。这状态用图3中X1、X2两点之间的曲线上的压力PD下降表示。在这一时间周期内,也可以保持压力PD大致不变。此后,燃油泵40压力侧的燃油压力进一步上升到大约500巴,克服第二喷咀11内的具有较大直径的弹簧18的关闭压力,从而针阀17也开启(点X2)。因此,从现在起,两 个喷咀1和11均开启,直到上止点后曲轴转角大约22°时,两喷咀才关阀,至此完成喷射作业。由于第二喷咀11的开启和与此相关的燃烧的强化,气缸44内的压力再度轻微上升。考虑整个喷射过程,就本发明的喷射过程而言,气缸44内的压力分布(曲线PZ44)较之公知的喷射过程的压力分布(曲线PZA)更为均匀。此外,整个喷射过程的压力分布是分段的。因为所述由燃油泵40产生的压力分布在第一喷咀喷射期间被保持着,X1和X2之间的时间间隔可借助于燃油泵驱动凸轮的适当形状加以控制。
偏离开所述示例性实施例,本发明的喷射过程也可采用两个以上的喷咀来完成,在此情况下,喷咀按前述关于燃烧室43中燃料喷注的式样配置。此时,首先仅第一喷咀开启,而其余的喷咀以后同时或也错开开启。
代替采用不同尺寸的关闭弹簧或预应力关闭弹簧,喷咀中针阀的开启运动通过电磁作用于针阀而被电子控制,也能达到喷咀的错开开启。
偏离于图3中所述喷射过程的改进,第一喷咀喷射开始也可处于上止点后。这取决于所谓的起燃跃变,即起燃压力和压缩压力之比。“压缩压力”应理解为在上止点时气缸中无燃烧的空气压缩压力。对于小的压力比,喷射开始可处于上止点后,而随着该压力比增大,逐移向上止点。

Claims (7)

1、一种用于将燃料喷入往复柴油内燃机气燃燃烧室内的过程,其中供给着火冲程的总燃料量用至少两个这样配置于燃烧室中的喷咀喷射,使正在离开每一喷咀的燃料喷注并不影响正在离另外相应喷咀的燃料喷注,其特征在于供给着火冲程的总燃料量喷射是这样进行的,起先,一个第一喷咀在气缸中被导向的工作活塞的上止点附近开启,而第二喷咀在第一喷咀仍然开启着的稍后时间里开启。
2、一种按权利要求1所述的燃料喷射过程,其特征在于在第一和第二喷咀开启之间的时间间隔通过影响这些喷咀端部的燃料压力而得以控制。
3、一种按权利要求1或2所述的燃料喷射过程,其特征在于第一和第二喷咀同时结束它们的喷射相位。
4、一种按权利要求1至3所述的燃料喷射过程,其特征在于第一和第二喷咀开启之间的时间周期为至少4°曲轴转角。
5、一种用于完成权利要求1所述的喷射过程的装置,其特征在于设置至少两个喷咀,它们在时间上错开开启,以喷射供给一个气缸着火冲程的总燃料量。
6、一种按权利要求5所述的喷射装置,它具有包括针阀的喷咀,针阀借助于燃油压力克服关闭弹簧的作用力而开启,其特征在于所述两喷咀包括不同刚度的关闭弹簧。
7、一种按权利要求5所述的喷射装置,它具有包括针阀的喷咀,针阀借助于燃油压力克服关闭弹簧的作用力而开启,其特征在于当所述关闭弹簧具有相同尺寸时,它们被施加不同的预应力。
CN93116413A 1992-09-11 1993-09-04 柴油内燃机中的燃料喷射过程 Expired - Lifetime CN1050878C (zh)

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EP92810700.2 1992-09-11
EP92810700A EP0586775B1 (de) 1992-09-11 1992-09-11 Verfahren zum Brennstoffeinspritzen bei Dieselbrennkraftmaschinen

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CN1087702A true CN1087702A (zh) 1994-06-08
CN1050878C CN1050878C (zh) 2000-03-29

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JP (1) JPH07133750A (zh)
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DK (1) DK0586775T3 (zh)

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GB1578131A (en) * 1976-05-14 1980-11-05 Lucas Industries Ltd Fuel supply systems for engines
JPS58186165U (ja) * 1982-06-04 1983-12-10 日産自動車株式会社 分配型燃料噴射ポンプ
JPH0637851B2 (ja) * 1984-01-10 1994-05-18 三菱重工業株式会社 デイーゼル機関の燃焼装置

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Publication number Priority date Publication date Assignee Title
CN103967673A (zh) * 2013-02-01 2014-08-06 马自达汽车株式会社 柴油发动机

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CN1050878C (zh) 2000-03-29
EP0586775A1 (de) 1994-03-16
DE59206823D1 (de) 1996-08-29
KR940007361A (ko) 1994-04-27
KR100322804B1 (ko) 2002-06-20
JPH07133750A (ja) 1995-05-23
EP0586775B1 (de) 1996-07-24
DK0586775T3 (da) 1996-08-26

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