【正文】 I 某型號(hào)液壓挖掘機(jī) （負(fù)載敏感系統(tǒng)）液壓系統(tǒng)設(shè)計(jì) 摘 要 液壓挖掘機(jī)是工程機(jī)械的一個(gè)重要品種，是一種廣泛用于建筑、鐵路、公路、水利、采礦等建設(shè)工程的土方機(jī)械。液壓挖掘機(jī)利用液壓元件（液壓泵、液壓馬達(dá)、液壓缸等）帶動(dòng)各種構(gòu)件動(dòng)作，具有許多優(yōu)點(diǎn)，于是它對(duì)液壓系統(tǒng)的設(shè)計(jì)提出了很高的要求，其液壓系統(tǒng)也是工程機(jī)械液壓系統(tǒng)中最為復(fù)雜的。因此，對(duì)挖掘機(jī)液壓系統(tǒng)的分析設(shè)計(jì)對(duì)推動(dòng)我國(guó)挖掘機(jī)發(fā)展具有十分重要的意義。 在搜集了國(guó)內(nèi)外挖掘機(jī)液壓系統(tǒng)相關(guān)資料的基礎(chǔ)上，了解了挖掘機(jī)液壓系統(tǒng)的發(fā)展歷史，并對(duì)挖掘機(jī)液壓系統(tǒng)的技術(shù)發(fā) 展動(dòng)態(tài)進(jìn)行了分析總結(jié)。本次畢業(yè)設(shè)計(jì)課題是負(fù)載敏感系統(tǒng)液壓挖掘機(jī)。挖掘機(jī)由多個(gè)系統(tǒng)組成，包括液壓系統(tǒng)，傳動(dòng)系統(tǒng)，操縱系統(tǒng)，工作裝置，底架，轉(zhuǎn)臺(tái)，油箱，發(fā)動(dòng)機(jī)安裝等。本人的設(shè)計(jì)主要致力于分析和設(shè)計(jì)負(fù)載敏感系統(tǒng)液壓挖掘機(jī)液壓系統(tǒng)的液壓站裝配圖，以液壓元件和液壓回路為主。 關(guān)鍵詞 ：挖掘機(jī)；液壓系統(tǒng)；液壓泵；負(fù)載敏感系統(tǒng) II Abstract Construction machinery hydraulic excavator is an important species, and it is widely used in construction, railway, highway, water conservancy, mining and other construction projects of Earthmoving Machinery. The use of hydraulic excavator hydraulic ponents (hydraulic pumps, hydraulic motors, hydraulic cylinders, etc.) bring a variety of ponent movement, has many advantages, so it is the design of the hydraulic system of the high demands, and its hydraulic system engineering machinery hydraulic system is the most plex. Therefore, the analysis of excavator hydraulic system design in promoting the development of China39。s excavator of great significance. At home and abroad in gathering relevant information excavator hydraulic system on the basis of the understanding of the excavators of the historical development of the hydraulic system, hydraulic excavators and technical developments have been analyzed and summarized. The graduation project is the subject of hydraulic excavators . Miniexcavator from multiple systems, including hydraulic system, transmission system, control system, the working devices, chassis, turntable, fuel tanks, engine installation were designed. I focused on the design of the analysis and design of smallsized hydraulic excavator hydraulic system hydraulic ponents such as hydraulic ponents and the main hydraulic circuit. Keywords: hydraulic pump。hydraulic system of excavator。Load sensitive system III 目 錄 摘 要 ........................................................... I Abstract .......................................................... II 1 緒 論 .......................................................... 1 液壓挖掘機(jī)工作裝置與液壓系統(tǒng)研究 的必要性 ................... 1 國(guó)內(nèi)外液壓挖掘機(jī)工作裝置的發(fā)展動(dòng)態(tài)及研究現(xiàn)狀 ............... 2 國(guó)外發(fā)展動(dòng)態(tài)及研究狀況 .............................. 2 國(guó)內(nèi)發(fā)展動(dòng)態(tài)及研究狀況 .............................. 3 國(guó)內(nèi)外液壓挖掘機(jī)液壓系統(tǒng)的發(fā)展動(dòng)態(tài)及研究現(xiàn)狀 ............... 4 國(guó)外發(fā)展動(dòng)態(tài)及研究狀況 .............................. 4 國(guó)內(nèi)研究情況及發(fā)展動(dòng)態(tài) .............................. 6 2 液壓挖掘機(jī)工作裝置的設(shè)計(jì)要求與傳統(tǒng)設(shè)計(jì)方法 ...................... 7 液壓挖掘機(jī)的工況分析 ....................................... 7 挖掘工況分析 ........................................ 8 滿(mǎn)斗舉升回轉(zhuǎn)工況分析 ............................... 12 卸載工況分析 ....................................... 12 空斗返回工況分析 ................................... 12 整機(jī)移動(dòng)工況分析 ................................... 12 姿態(tài)調(diào)整與保持工況分析 ............................. 13 液壓挖掘機(jī)工作裝置的設(shè)計(jì)要求 .............................. 13 幾何尺寸要求 ....................................... 13 各功能運(yùn)動(dòng)的動(dòng)力特性要求 ........................... 14 結(jié)構(gòu)強(qiáng)度要求 ....................................... 15 經(jīng)濟(jì)性要求 ......................................... 16 其它 性能要求 ....................................... 16 液壓挖掘機(jī)的主要參數(shù) ...................................... 16 描述挖掘機(jī)性能的主要參數(shù) ........................... 16 液壓挖掘機(jī)的主參數(shù) ................................. 17 液壓挖掘機(jī)工作裝置的傳統(tǒng)設(shè)計(jì)方法分析 ...................... 17 通過(guò)類(lèi)比及經(jīng)驗(yàn)方法的工作裝置的設(shè)計(jì) ................. 17 基于計(jì)算機(jī)輔助設(shè)計(jì)方法的工作裝置的設(shè)計(jì) ............. 17 3 液壓系統(tǒng)設(shè)計(jì) ................................................... 19 系統(tǒng)主參數(shù)的確定 .......................................... 19 確定系統(tǒng)的工作壓力 ................................. 19 確定系統(tǒng)的型式 ..................................... 20 系統(tǒng)方案的擬定 ............................................ 20 確定元件類(lèi)型 ....................................... 20 擬定主回路 ......................................... 21 4 系統(tǒng)初步計(jì)算和液壓元件的選擇 ................................... 22 動(dòng)臂液壓缸的設(shè)計(jì)計(jì)算 ...................................... 22 液壓缸缸筒的設(shè)計(jì) ................................... 22 IV 液壓缸缸蓋及導(dǎo)向套的設(shè)計(jì) ........................... 24 液壓缸缸頭的設(shè)計(jì) ................................... 27 活塞桿的設(shè)計(jì)及其強(qiáng)度校核 ........................... 29 活塞的設(shè)計(jì) ......................................... 31 缸筒長(zhǎng)度的確定 ..................................... 33 缸頭的結(jié)構(gòu)設(shè)計(jì) ..................................... 33 活塞桿長(zhǎng)度的確定 ................................... 35 液壓缸縱向彎曲極限應(yīng)力的計(jì)算和穩(wěn)定性校核 ........... 35 液壓缸油口尺寸的確定 ............................... 37 密封和防塵裝置的作用及選取 ......................... 38 緩沖裝置 ........................................... 38 斗桿液壓缸的設(shè)計(jì) .......................................... 38 鏟斗液壓缸的設(shè)計(jì) .......................................... 38 推土鏟液壓缸的設(shè)計(jì) ........................................ 39 液壓缸推力和流量的計(jì)算 .................................... 39 液壓缸推力計(jì)算 ..................................... 39 液壓缸的輸出功率 ................................... 40 液壓缸流量 ......................................... 40 5 液壓泵與馬達(dá)的選用 ............................................. 41 液 壓泵的流量計(jì)算 .......................................... 41 液壓缸動(dòng)作所需流量 ........................................ 41 行走機(jī)構(gòu)所需流量 .......................................... 41 回轉(zhuǎn)機(jī)構(gòu)所需流量 .......................................... 42 液壓泵的選擇 .............................................. 44 6 液壓泵站設(shè)計(jì)及液壓附件的選取 ................................... 45 液壓閥的選取 .............................................. 45 液壓泵站的設(shè)計(jì) ......................