不同的制動驅動在汽車前橋中的應用
2020-05-19 17:59:39 人氣：1160
汽(qi)車制(zhi)動(dong)(dong)(dong)驅動(dong)(dong)(dong)機構和制(zhi)動(dong)(dong)(dong)力(li)調(diao)節機構來自駕駛(shi)員或其它力(li)源(yuan)的力(li)傳給制(zhi)動(dong)(dong)(dong)器，使之產生制(zhi)動(dong)(dong)(dong)力(li)矩。根據制(zhi)動(dong)(dong)(dong)力(li)源(yuan)的不(bu)同(tong)，前橋(qiao)前橋(qiao)制(zhi)動(dong)(dong)(dong)驅動(dong)(dong)(dong)機構一般可(ke)分為簡單(dan)制(zhi)動(dong)(dong)(dong)、動(dong)(dong)(dong)力(li)制(zhi)動(dong)(dong)(dong)和伺(si)服(fu)制(zhi)動(dong)(dong)(dong)三(san)大類(lei)。
簡(jian)單(dan)制(zhi)(zhi)動(dong)(dong)(dong)單(dan)靠(kao)駕(jia)駛員施加(jia)的(de)踏(ta)板或手柄作(zuo)(zuo)為制(zhi)(zhi)動(dong)(dong)(dong)力(li)源，故亦稱(cheng)為人(ren)力(li)制(zhi)(zhi)動(dong)(dong)(dong)。其中，又(you)分為機(ji)(ji)械(xie)式(shi)(shi)和(he)液(ye)(ye)壓(ya)式(shi)(shi)兩種。機(ji)(ji)械(xie)式(shi)(shi)完全靠(kao)桿系傳(chuan)力(li)，由(you)于其機(ji)(ji)械(xie)效(xiao)率(lv)低，傳(chuan)動(dong)(dong)(dong)比(bi)小，潤滑點多，切難以(yi)(yi)保(bao)證前、后軸制(zhi)(zhi)動(dong)(dong)(dong)力(li)的(de)正確比(bi)例和(he)左、右輪(lun)制(zhi)(zhi)動(dong)(dong)(dong)力(li)的(de)均衡(heng)，所以(yi)(yi)在汽車(che)的(de)行車(che)制(zhi)(zhi)動(dong)(dong)(dong)裝(zhuang)置(zhi)(zhi)中以(yi)(yi)被淘(tao)汰。但因其結構簡(jian)單(dan)，成(cheng)本低，工作(zuo)(zuo)可靠(kao)（故障少），還廣泛的(de)應用(yong)于中，小汽車(che)的(de)駐車(che)制(zhi)(zhi)動(dong)(dong)(dong)裝(zhuang)置(zhi)(zhi)中。 液(ye)(ye)壓(ya)式(shi)(shi)簡(jian)單(dan)制(zhi)(zhi)動(dong)(dong)(dong)（通常(chang)稱(cheng)為液(ye)(ye)壓(ya)制(zhi)(zhi)動(dong)(dong)(dong)）用(yong)于行車(che)制(zhi)(zhi)動(dong)(dong)(dong)裝(zhuang)置(zhi)(zhi)。液(ye)(ye)壓(ya)制(zhi)(zhi)動(dong)(dong)(dong)的(de)優點是：作(zuo)(zuo)用(yong)滯后時間較短(duan)（0.1～0.3s）；工作(zuo)(zuo)壓(ya)力(li)高（可達10～20MPa），因而輪(lun)缸尺寸小，可以(yi)(yi)安裝(zhuang)在制(zhi)(zhi)動(dong)(dong)(dong)器(qi)內部，直接(jie)作(zuo)(zuo)為制(zhi)(zhi)動(dong)(dong)(dong)蹄的(de)張(zhang)開機(ji)(ji)構（或制(zhi)(zhi)動(dong)(dong)(dong)塊的(de)壓(ya)緊機(ji)(ji)構），而不需(xu)要制(zhi)(zhi)動(dong)(dong)(dong)臂等傳(chuan)動(dong)(dong)(dong)件，使(shi)之結構簡(jian)單(dan)，質量小；機(ji)(ji)械(xie)效(xiao)率(lv)高（液(ye)(ye)壓(ya)制(zhi)(zhi)動(dong)(dong)(dong)系統有(you)自(zi)潤滑作(zuo)(zuo)用(yong)）。液(ye)(ye)壓(ya)制(zhi)(zhi)動(dong)(dong)(dong)的(de)主要確定是過度受熱后，部分制(zhi)(zhi)動(dong)(dong)(dong)液(ye)(ye)汽化，在管路中形成(cheng)氣泡，嚴重影響(xiang)液(ye)(ye)壓(ya)傳(chuan)輸(shu)使(shi)制(zhi)(zhi)動(dong)(dong)(dong)系效(xiao)能(neng)降低，甚至完全失效(xiao)。
動(dong)(dong)(dong)(dong)(dong)力(li)(li)(li)(li)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)即(ji)(ji)利用(yong)(yong)發(fa)動(dong)(dong)(dong)(dong)(dong)機(ji)(ji)的(de)(de)(de)(de)動(dong)(dong)(dong)(dong)(dong)力(li)(li)(li)(li)轉化而成，并表現為(wei)氣(qi)壓(ya)(ya)或液壓(ya)(ya)形式(shi)的(de)(de)(de)(de)勢能作為(wei)汽車制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)(de)全部(bu)力(li)(li)(li)(li)源。駕駛員施(shi)加于(yu)(yu)踏板(ban)(ban)或手柄上(shang)(shang)的(de)(de)(de)(de)力(li)(li)(li)(li)，僅用(yong)(yong)于(yu)(yu)回路中(zhong)控制(zhi)(zhi)(zhi)(zhi)元(yuan)件的(de)(de)(de)(de)操(cao)縱。因(yin)(yin)此(ci)(ci)，簡(jian)單制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)中(zhong)的(de)(de)(de)(de)踏板(ban)(ban)力(li)(li)(li)(li)和(he)(he)踏板(ban)(ban)行程之(zhi)間(jian)的(de)(de)(de)(de)反(fan)比例關系，在(zai)動(dong)(dong)(dong)(dong)(dong)力(li)(li)(li)(li)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)中(zhong)便不(bu)復存在(zai)，從而可使(shi)踏板(ban)(ban)力(li)(li)(li)(li)較(jiao)小，同時(shi)又有適當的(de)(de)(de)(de)踏板(ban)(ban)行程。 氣(qi)壓(ya)(ya)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)是(shi)應用(yong)(yong)最多的(de)(de)(de)(de)動(dong)(dong)(dong)(dong)(dong)力(li)(li)(li)(li)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)之(zhi)一(yi)。其(qi)主要(yao)優點為(wei)操(cao)縱輕便、工作可輕型貨車前橋總成設計可靠、不(bu)易出故障、維修保養方(fang)便；此(ci)(ci)外(wai)，其(qi)氣(qi)源除供(gong)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)用(yong)(yong)外(wai)，還可以供(gong)其(qi)它裝置(zhi)使(shi)用(yong)(yong)。 其(qi)主要(yao)缺點是(shi)必須有空氣(qi)壓(ya)(ya)縮(suo)機(ji)(ji)、貯氣(qi)筒、制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)閥等(deng)裝置(zhi)，結構(gou)復雜、笨重(zhong)、成本高；管路中(zhong)壓(ya)(ya)力(li)(li)(li)(li)的(de)(de)(de)(de)建立和(he)(he)撤除都較(jiao)慢，即(ji)(ji)作用(yong)(yong)滯(zhi)后時(shi)間(jian)長(chang)（0.3～0.9s），因(yin)(yin)而增加了(le)空駛距(ju)離和(he)(he)停車距(ju)離，為(wei)此(ci)(ci)在(zai)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)閥到制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)氣(qi)室和(he)(he)貯氣(qi)筒的(de)(de)(de)(de)距(ju)離過遠(yuan)的(de)(de)(de)(de)情況下，有必要(yao)加設氣(qi)動(dong)(dong)(dong)(dong)(dong)的(de)(de)(de)(de)第二級(ji)元(yuan)件。管路工作壓(ya)(ya)力(li)(li)(li)(li)低，一(yi)般為(wei)0.5～0.7MPa，因(yin)(yin)而制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)氣(qi)室的(de)(de)(de)(de)直(zhi)徑必須設計得(de)(de)大些，且(qie)只能置(zhi)于(yu)(yu)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)器外(wai)部(bu)，太通過桿件和(he)(he)凸(tu)輪或楔塊(kuai)驅動(dong)(dong)(dong)(dong)(dong)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)蹄，這(zhe)就增加了(le)簧下質量；制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)氣(qi)室排氣(qi)有很大的(de)(de)(de)(de)噪聲。氣(qi)壓(ya)(ya)制(zhi)(zhi)(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)在(zai)總質量8噸以上(shang)(shang)的(de)(de)(de)(de)貨車和(he)(he)客車上(shang)(shang)得(de)(de)到廣泛(fan)的(de)(de)(de)(de)應用(yong)(yong).
