【正文】 小時(shí)，換向閥再換到左位，實(shí)現(xiàn)平穩(wěn)卸荷。當(dāng)活塞以恒定的速度移動到一定位置時(shí)，行程閥接受到信號，并產(chǎn)生動作，實(shí)現(xiàn)由快進(jìn)到工進(jìn)的轉(zhuǎn)換。其工進(jìn)速度由一個(gè)調(diào)速閥來控制。因?yàn)榘辶险蹚潤C(jī)的工作循環(huán)為快速下降、慢速加壓（折彎）、快速回程三個(gè)階段。 analysis and grafting production actual problem ability, for the design of future work to lay a good foundation. 3, by design, drawing, calculation, students should apply and be familiar with the design data ( including design, product samples, standards and norms ) and estimates of practical training. Key words: sheet metal bending machine, hydraulic system, hydraulic transmission course design. 攀枝花學(xué)院學(xué)生設(shè)計(jì)（論文） 目 錄 目錄 摘 要 .............................................................................................................................. ABSTRACT ....................................................................................................................... I 1 任務(wù)分析 ................................................................................................................. 1 技術(shù)要求 ............................................................................................................................... 1 任務(wù)分析 ............................................................................................................................... 1 2 工況分析 ................................................................................................................. 3 運(yùn)動分析 ............................................................................................................................... 3 負(fù)載分析 ............................................................................................................................... 3 確定液壓缸主要尺寸，編制液壓缸工況圖 ....................................................................... 5 ....................................................................................... 5 編制液壓缸工況圖 ................................................................................................................ 6 3 擬定液壓系統(tǒng)圖 ..................................................................................................... 9 制定基本方案， 擬定液壓系統(tǒng)圖 ........................................................................................ 9 4 液壓元件選型 .......................................................................................................... 10 液壓泵及其驅(qū)動電機(jī)的選擇 .............................................................................................. 10 閥類元件及輔助元件 .......................................................................................................... 10 油管元件 ............................................................................................................................. 11 油箱的容積計(jì)算 .................................................................................................................. 12 油箱的長寬高 ...................................................................................................................... 12 油箱地面傾斜度 .................................................................................................................. 13 吸油管和過濾器之間管接頭的選擇 .................................................................................. 13 過濾器的選取 ...................................................................................................................... 13 堵塞的選取 .......................................................................................................................... 13 空氣過濾器的選取 ............................................................................................................ 13 液位 /溫度計(jì)的選取 .......................................................................................................... 14 5 液壓系統(tǒng)性能的運(yùn)算 ........................................................................................... 15 壓力損失和調(diào)定壓力的確定 ........................................................................................... 15 沿程壓力損失 ........................................................................................................... 15 壓力閥的調(diào)定值計(jì)算 .................................................................................................. 16 油液溫升的計(jì)算 ................................................................................................................. 16 快退時(shí)液壓缸的發(fā)熱量 ............................................................................................... 0 壓制時(shí)液壓缸的發(fā)熱量 ................................................................................................ 0 油箱的設(shè)計(jì) ............................................................................................................................ 0 系統(tǒng)發(fā)熱量的計(jì)算 ........................................................................................................ 0 散熱量的計(jì)算 .....................