【正文】 要求，實(shí)際上可理解為是對(duì)由凸輪外形所決定的氣門位移規(guī)律的要求。 一般說來，設(shè)計(jì)合理的配氣機(jī)構(gòu)應(yīng)具有良好的換氣性能，進(jìn)氣充分，排氣徹底，即具有較大的時(shí)間 斷面值，泵氣損失小， 配氣正時(shí)恰當(dāng)。由于在實(shí)際工作中，壓力，溫度都有不利因素，所以充量系數(shù)總是小于 1，一般在 — 。充量系數(shù)越高，表明進(jìn)入氣缸內(nèi)的新鮮空氣或可燃混合氣的質(zhì)量越多，發(fā)動(dòng)機(jī)發(fā)出的功率越大。 配氣機(jī)構(gòu)的功用是按照發(fā)動(dòng)機(jī)每一氣缸內(nèi)所進(jìn)行的工作循環(huán)和發(fā)火次序的要求，定時(shí)開啟和關(guān)閉進(jìn)、排氣門，使新鮮充量得以及時(shí)進(jìn)入氣缸，而廢氣得以及時(shí)從氣缸排出。 配氣機(jī)構(gòu)設(shè)計(jì)的優(yōu)劣不僅影響發(fā)動(dòng)機(jī)的結(jié)構(gòu)緊湊性和制造、使用的成本，而且還決定了高速運(yùn)轉(zhuǎn)時(shí)柴油機(jī)的工作可靠性、耐久性。它的功能是實(shí)現(xiàn)換氣過程，即根據(jù)氣缸的工作次序，定時(shí)地開啟和關(guān)閉進(jìn)、排氣門，以保證氣缸吸入新鮮空氣和排除燃燒廢氣 。 Cam profile。 關(guān)鍵詞： 內(nèi)燃機(jī)；配氣機(jī)構(gòu)；凸輪型線； 全套圖紙，加 153893706 II ABSTRACT The valve train is one of the most important mechanisms in a internal bustion engine, whether the performances are good or bad, that affecting the power performance, economic performance, emissions performance of the engine, as well as affecting the reliability and wear performances of the whole engine. Along with the requests of the engine’ s high power, superspeed, people demand a higher index. That is, when the engine runs under a high speed, it can still work steadily and dependably, which demand that the valve train system should have a high performance. Cam profile is the hard core of the valve train, which design is one of the important ways to carry out valve train optimal design. Simulation calculation and experimentation research are two important ways to carry out research and development on valve train of internalbustion engine. Key words:Internal bustion engine。配氣凸輪型線是配氣機(jī)構(gòu)的核心部分，配氣凸輪型線設(shè)計(jì)是配氣機(jī)構(gòu)優(yōu)化設(shè)計(jì)的重要途徑之一。 I 摘要 配氣機(jī)構(gòu)作為內(nèi)燃機(jī)的重要組成部分，其設(shè)計(jì)合理與否直接關(guān)系到內(nèi)燃機(jī)的動(dòng)力性能、經(jīng)濟(jì)性能、排放性能及工作的可靠性、耐久性。隨著內(nèi)燃機(jī)高功率、高速化，人們對(duì)其性能指標(biāo)的要求越來越高，要求其在高速運(yùn)行的條件下仍然能夠平穩(wěn)、可靠地工作，因而對(duì)其配氣機(jī)構(gòu)提出了更高的要求。模擬計(jì)算和實(shí)驗(yàn)研究是內(nèi)燃機(jī)配氣機(jī)構(gòu)研究?jī)煞N重要手段。 Valve train。 III 目 錄 摘要 ....................................................................................................................................................... I ABSTRACT ........................................................................................................................................ II 第 1章 緒 論 ................................................................................................................................. 1 概述 ....................................................................................................... 1 配氣機(jī)構(gòu)的研究歷程 .......................................................................... 2 配氣機(jī)構(gòu)優(yōu)化設(shè)計(jì)的目的及意義 ........................................................ 2 配氣機(jī)構(gòu)采用的新技術(shù) ........................................................................ 3 頂置凸輪軸技術(shù) ......................................................................... 3 多氣門技術(shù) ................................................................................ 4 可變氣門正時(shí)配氣機(jī)構(gòu) ............................................................ 5 本章小結(jié) ................................................................................................ 5 第 2章 配氣機(jī)構(gòu)的總體布置 ........................................................................................................ 6 氣門的布置形式 ................................................................................... 6 凸輪軸的布置形式 ............................................................................... 6 凸輪軸的傳動(dòng)方式 ............................................................................... 6 每缸氣門數(shù)及其排列方式 ................................................................... 6 氣門間隙 ............................................................................................... 7 本章小結(jié) ............................................................................................... 7 第 3章 配氣正時(shí)的工作原理 .......................................................................................................... 8 配氣正時(shí)的介紹 .................................................................................... 8 工作原理 ................................................................................................ 8 本章小結(jié) ................................................................................................ 9 第 4章 配氣機(jī)構(gòu)的零件及組件 .................................................................................................... 10 氣門組 ................................................................................................. 10 氣門 .......................................................................................... 10 氣門座圈 .................................................................................. 15 氣門導(dǎo)管 .................................................................................. 15 彈簧設(shè)計(jì)計(jì)算 .......................................................................... 16 氣門傳動(dòng)組 ......................................................................................... 21 凸輪軸 ...................................................................................... 21 IV 凸輪型線設(shè)計(jì) .......................................................................... 21 緩沖段設(shè)計(jì) .............................................................................. 23 凸輪軸進(jìn)排氣凸輪角度設(shè)計(jì) .................................................. 24 基本段設(shè)計(jì) .............................................................................. 24 曲軸正時(shí)鏈輪與凸輪軸正時(shí)鏈輪 .......................................... 26 挺柱 .......................................................................................... 26 第 5章 正時(shí)鏈設(shè)計(jì)方法 ................................................................................................................ 27 汽車鏈服役條件及失效形式 .............................................................. 27 汽車鏈的服役條件 ................................................................. 27 汽車鏈的失效形式 ................................................................... 27 汽車鏈的選擇 ...................................................................................... 28 汽車鏈傳動(dòng)系統(tǒng)設(shè)計(jì) .......................................................................... 29 本章小結(jié)