目
录
1.1 选题意义...................................................................................................................................................3
1.2 挖掘机及其液压技术概述.......................................................................................................................3
1.3 国内外研究现状.......................................................................................................................................4
1.4 挖掘机发展趋势.......................................................................................................................................5
挖掘机液压系统概述.........................................................................................6
2.1 挖掘机液压系统的基本组成及其基本要求...........................................................................................6
2.2 挖掘机液压系统的基本动作分析...........................................................................................................7
2.3 挖掘机液压系统的基本回路分析...........................................................................................................8
2.3.1 限压回路........................................................................................................................................8
2.3.2 缓冲回路.......................................................................................................................................9
2.3.3 节流回路......................................................................................................................................10
2.3.4 行走限速回路..............................................................................................................................11
2.3.5 合流回路.....................................................................................................................................13
2.3.6 闭锁回路.....................................................................................................................................14
2.3.7 再生回路......................................................................................................................................14
挖掘机液压系统设计.......................................................................................15
3.1 挖掘机的功用和对液压系统的要求.....................................................................................................15
3.2 挖掘机液压系统分析.............................................................................................................................16
3.2.1 挖掘机的液压系统原理图..........................................................................................................16
3.2.2 系统工作循环分析......................................................................................................................17
3.2.3 主要液压元件在系统中的作用..................................................................................................18
3.2.4 液压系统中几种低压回路的作用..............................................................................................18
4.1 计算所需要的泵的流量.........................................................................................................................20
4.2 回转台启动力矩和制动力矩.................................................................................................................22
4.2 泵的选择.................................................................................................................................................25
4.3 油箱容积计算.........................................................................................................................................25
4.4 油管尺寸计算.........................................................................................................................................25
4.5 热平衡验算.............................................................................................................................................26
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