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1.
正凸轮轴是发动机的重要零件,是配气机构的一部分,专门负责驱动气门按时开启和关闭,加工难度大,用量大,消耗大。我国汽车凸轮轴开发较早,经过几十年努力,目前凸轮轴行业已步入正轨,市场产量逐年增长。国内已出现一批骨干企业。在这些骨干企业中,凸轮轴企业在生产能力、制造技术和经营管理水平等方面的表现非常突出,已形成了较高的企业整体素质。中汽成都配件有限公司(如下简称中汽成都配件)就是其中之一。 相似文献
2.
论述了凸轮轴的发展背景及其加工工艺,所用材料用途等。介绍了凸轮轴的制造技术,使用范围及国内外的生产技术现状和发展趋势。气门运动规律关系到一台发动机的动力和运转特性,因此,凸轮轴设计在发动机的设计过程中占据着十分重要的地位。 相似文献
3.
凸轮轴作为发动机三大关键摩擦副之一,是发动机配气机构中气门传动组最关键的零部件。凸轮轴结构设计与加工质量的好坏,直接影响发动机的性能。装配式凸轮轴制造工艺作为一种先进制造技术,以其构思新颖、经济和社会效益显著等优点,满足了现代企业发 相似文献
4.
伊顿因其发动机空气管理而闻名世界。在过去的80年来,伊顿始终是发动机气门和气门驱动产品的最大生产商之一,其气门和气门驱动技术被世界各地的汽车制造商选中来提高燃油经济性和发动机整体性能。主要产品包括:发动机气门、液压挺柱及滚子摇臂、可变气门驱动系统、发动机停缸技术、油泵挺筒等。日前,动力管理公司伊顿在第十六届上海国际汽车工业展览会上展示了12挡机械式自动变速箱、车载加油油气回收系统、气缸停缸系统和基于4挡变速箱的纯电驱动系统等。 相似文献
5.
集团公司最近推出一款新型发动机,采用直列四缸、单缸四气门结构,双顶置凸轮轴,平底挺柱(无摇臂,凸轮轴直接作用在挺柱上带动气门工作),排气量为1.3L和1.5L两个系列。此发动机性能优良,技术在国内同款发动机中处于先进水平。为缩短生产周期,降低加工成本,该新款发动机金属切削加工中广泛采用高速切削加工技术以及最新工艺、最先进刀具。 相似文献
6.
凸轮轴是摩托车、汽车、飞机等发动机的核心部件,它的功能是保证发动机正确的配气相位和按一定运动规律控制气门组定时开、闭。 凸轮轴上各凸轮的位置和形状是影响气门开闭间隙大小和配气效率的主要因素。目前,在凸轮轴的加工已广泛采用自动线生产的条件下,传统的检测方法、检测数据要人工处理,信息量大、效率低, 相似文献
7.
配气机构是发动机的重要组成部分,其性能的优劣决定着发动机性能。文中从发动机目前使用的配气机构技术、配气机构优化参数以及配气机构优化方式等几个方面介绍了国内外配气机构发展现状和发展趋势。配气机构将会朝着气门升程、配气相位及进气管都可变的全可变技术和无凸轮轴可变技术方向发展。 相似文献
8.
凸轮轴是发动机配气机构的一部分,通过摇臂驱动气门按时开起和关闭,保证发动机在工作中定时为气缸吸入新鲜的可燃混合气,并及时将燃烧后的废气排也气缸。 相似文献
9.
发动机采用可变气门正时技术可以提高进气克量,使充量系数增加,发动机的扭矩和功率可以得到进一步的提高.文章分析了本田VTEC发动机的可变气门正时技术.研制了一种组合式正时凸轮轴.可以灵活改变凸轮外轮廓(即凸轮曲线)的长度,改变气门的开起时间和气门处于最大开口的持续时间,可以改善发动机的配气效果. 相似文献
10.
凸轮轴是汽车发动机关键部件之一,主要由凸轮、支承轴颈、轴颈等几部分组成(见图1)。凸轮轴的作用是控制气门的开启和闭合动作,其制造品质影响发动机的功率指标、排放指标、节油指标等。目前,在我国发动机凸轮轴的制造方法中通常有两种: 相似文献
11.
飞机多电化时代已经到来,飞机发动机、发电机、配电系统、用电系统、环控系统、作动系统、起降转弯刹车系统以及其他机载系统都在发生着多电化的变化。该文从多电化趋势阐述集成电动静液作动器的国外研发现状,介绍了集成电动静液作动系统的组成原理、相关理论和关键技术。 相似文献
12.
Electromagnetic valve (EMV) actuation system is a new technology for improving fuel efficiency and at the same time reducing
emissions in internal combustion engines. It can provide more flexibility in valve event control compared with conventional
variable valve actuation devices. The electromagnetic valve actuator must be designed by taking the operating conditions and
engine geometry limits of the internal combustion engine into account. To help develop a simple design method, this paper
presents a procedure for determine the basic design parameters and dimensions of the actuator from the relations of the valve
dynamics, electromagnetic circuit and thermal loading condition based on the lumped method. To verify the accuracy of the
lumped method analysis, experimental study is also carried out on a prototype actuator. It is found that there is a relatively
good agreement between the experimental data and the results of the proposed design procedure. Through the whole speed range,
the actuator maintains proper performances in valve timing and event control. 相似文献
13.
Various technologies are being studied for the advancement of diesel passenger cars and associated environmental regulations. Effective compression ignition combustion in diesel engines is highly dependent on the cylinder charging temperature, composition, and cylinder pressure during valve train operation. The application of variable valve control in diesel engines has several potential advantages. In this study, we applied the variable valve actuation system to a single-cylinder engine model using a GT-POWER simulation and analyzed the effects of the recompression and rebreathing valve profiles, and fuel-injection pressure on the combustion characteristics of a compression ignition engine. As a result, NOx emissions were reduced by more than 90 %, while those of indicated mean effective pressure were reduced by up to 35 %. The benefits of recompression strategies in terms of NOx emissions reduction were confirmed. 相似文献
14.
Hydraulic actuators are important in modern industry due to high power, fast response, and high stiffness. In recent years,
hybrid actuation system, which combines electric and hydraulic technology in a compact unit, can be adapted to a wide variety
of force, speed and torque requirements. Moreover, the hybrid actuation system has dealt with the energy consumption and noise
problem existed in the conventional hydraulic system. Therefore, hybrid actuator has a wide range of application fields such
as plastic injection-molding and metal forming technology, where force or pressure control is the most important technology.
In this paper, the solution for force control of hybrid system is presented. However, some limitations still exist such as
deterioration of the performance of transient response due to the variable environment stiffness. Therefore, intelligent switching
control using Learning Vector Quantization Neural Network (LVQNN) is newly proposed in this paper in order to overcome these
limitations. Experiments are carried out to evaluate the effectiveness of the proposed algorithm with large variation of stiffness
of external environment. In addition, it is understood that the new system has energy saving effect even though it has almost
the same response as that of valve controlled system. 相似文献
15.
In-vehicle driving tests for evaluating the performance and diagnostic functionalities of engine control systems are often time consuming, expensive, and not reproducible. Using a hardware-in-the-loop (HIL) simulation approach, new control strategies and diagnostic functions on a controller area network (CAN) line can be easily tested in real time, in order to reduce the effort and the cost of the testing phase. Nowadays, spark ignition engines are controlled by an electronic control unit (ECU) with a large number of embedded sensors and actuators. In order to meet the rising demand of lower emissions and fuel consumption, an increasing number of control functions are added into such a unit. This work aims at presenting a portable electronic environment system, suited for HIL simulations, in order to test the engine control software and the diagnostic functionality on a CAN line, respectively, through non-regression and diagnostic tests. The performances of the proposed electronic device, called a micro hardware-in-the-loop system, are presented through the testing of the engine management system software of a 1.6 l Fiat gasoline engine with variable valve actuation for the ECU development version. 相似文献
16.
目前AMT伺服系统大多采用液压或者电机驱动,与这两种方式相比,气动系统具有安全、环保、动作较快等优势。作为其核心控制元件,高速开关阀的性能决定了系统的整体性能。以阀的动作频率、线圈温升与声速流导为指标,设计了一种高速开关阀。首先通过计算确定了阀的主要尺寸及参数,然后仿真分析了阀的动静态电磁特性、阀芯位移响应曲线与阀的温度场,结果表明,阀的动作频率与线圈温升均满足设计要求;接着,对影响阀性能的参数进行了因素分析,根据分析结果进行了多目标参数优化,既降低了线圈功耗与温升,又满足了设计要求;最后通过实验验证了第一代阀基本满足设计要求。 相似文献
17.
对比现有泵阀联合控制方案,针对调速电动机 阀联合控制方案,提出了分级压力控制和负载敏感控制,并详细论述了工作原理。该方案兼顾效率与响应并充分考虑现有技术,对目前作动系统设计具有更为实际的意义。 相似文献
18.
In a fuel supply system of gasoline engines, a part of the fuel ejected from the carburetor floats in flow with high speed as dro plets in an intake manifold and the rest of it flows as the liquid film along the wall of the intake manifold and is gradually vaporized in the flow. Finally, most part of the fuel terminates the vaporization after introducing mixture into cylinders. Accordingly, it is desirable to maintain the optimum mixture ratio in conventional carburetor systems for all operating conditions of engines. The intake system including the carburetor of automotive gasoline engines which are mostly operating in partload conditions have many unsolved problms, such as the increase of specific fuel consumption and reduction of exhaust emissions due to the rich mixture in starting, acceleration and over load operations. Therefore the main purpose of the study is to develop a special device (so called Eco-Ring) for the enhancement of atomization that has ability to separate the liquid film spray flowing along the pipe wall of the intake manifold and to atomize it to fine droplets, then the device can overcome some defects which arise in the conventional carburetor systems as mentioned above. 相似文献
19.
燃料供给的实时、精确调节是冲压发动机技术研究的重点,对提高发动机的效率、改善发动机的工作性能具有重要的意义。为实现冲压发动机气态燃料在高温下流量的精确调节,提出了一种新型的拉瓦尔式燃料流量调节阀,以对流入发动机燃烧室的高温气态燃料进行流量调节。首先,开发了一种用于燃料供应的高温流量调节阀,然后通过采用有限元分析方法,分析了流经主阀阀口的气态燃料速度及压力的分布,从而找出了流量变化规律。研究结果表明,采用拉瓦尔管状阀口的流量调节阀,在不改变阀芯位移量以及一定入口压力条件下,流经阀口的燃料流量保持不变,且与出口压力无关。 相似文献
20.
以某1.5 L增程式发动机为研究对象,建立并标定其CAE仿真模型,利用实验设计(DOE)技术对气门升程曲线、进气歧管及进气道结构进行优化研究;对改型后的增程式发动机进行了全面的台架试验标定。实验和分析结果表明:新的气门升程曲线提高了低速段扭矩,尤其是转速为1200r/min和2800r/min时,扭矩分别增大了10%和12%;优化了进气道结构,平均滚流比大幅提升至原来的1.5~2.2倍;优化后的增程式发动机高效率区的实验等油耗值为250g/(kW·h),相对原机的实验等油耗值,增加了近3倍。 相似文献
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