一、行程開關工作原理是什么

行(xing)程開關是(shi)主令電器里的一(yi)種，其動作(zuo)(zuo)原理和按鈕沒有(you)什么(me)差別(bie)(bie)，主要區(qu)別(bie)(bie)是(shi)：它不(bu)是(shi)用(yong)手進行(xing)按壓操(cao)作(zuo)(zuo)而(er)是(shi)用(yong)機械設備的一(yi)些運動部(bu)件與它的傳動部(bu)位發(fa)生碰撞(zhuang)，來促使行(xing)程開關的觸頭(tou)動作(zuo)(zuo)的（常(chang)開觸點閉合，常(chang)閉觸點斷(duan)開），能夠(gou)達到分斷(duan)或者切換電路的目(mu)的。

行(xing)程(cheng)開關(guan)工作時，利(li)用內部的元件(jian)碰撞，達(da)到開啟電路或關(guan)閉(bi)電路的功(gong)能。正常情況下(xia)，行(xing)程(cheng)開關(guan)一旦開啟，便會(hui)給機(ji)(ji)械(xie)運(yun)(yun)動添加上(shang)一個運(yun)(yun)動的軌(gui)跡，只要機(ji)(ji)械(xie)達(da)到設定的位置，便會(hui)自動停止運(yun)(yun)轉(zhuan)，或是改變運(yun)(yun)動狀態，從(cong)而達(da)到開關(guan)的目的。

二、不同結構的行程開關原理

行程開關(guan)按(an)結構分主(zhu)要(yao)可分為三種，三種行程開關(guan)的原理有所(suo)不同：

1、直動式行程開關結構原理

直動(dong)(dong)式行程(cheng)開(kai)關由(you)推桿(gan)、彈簧、動(dong)(dong)斷(duan)觸(chu)點和動(dong)(dong)合觸(chu)點組成，工作時，由(you)運動(dong)(dong)部件(jian)(jian)(jian)的撞(zhuang)塊(kuai)碰(peng)撞(zhuang)，當(dang)外界運動(dong)(dong)部件(jian)(jian)(jian)上的撞(zhuang)塊(kuai)碰(peng)壓按鈕(niu)使其觸(chu)頭動(dong)(dong)作，當(dang)運動(dong)(dong)部件(jian)(jian)(jian)離開(kai)后(hou)，在彈簧作用下，其觸(chu)頭自(zi)動(dong)(dong)復(fu)位。

2、滾輪式行程開關結構原理

滾(gun)(gun)動(dong)(dong)(dong)(dong)(dong)式(shi)行(xing)(xing)程(cheng)開(kai)(kai)關的(de)(de)結(jie)構比較(jiao)復雜，由滾(gun)(gun)輪(lun)(lun)(lun)、上(shang)轉臂、彈(dan)簧(huang)、套(tao)架(jia)、滑輪(lun)(lun)(lun)、壓板(ban)、觸點和橫板(ban)組成(cheng)；工作時(shi)(shi)，當(dang)(dang)運動(dong)(dong)(dong)(dong)(dong)機械的(de)(de)擋(dang)鐵(tie)（撞塊(kuai)）壓到(dao)行(xing)(xing)程(cheng)開(kai)(kai)關的(de)(de)滾(gun)(gun)輪(lun)(lun)(lun)上(shang)時(shi)(shi)，傳動(dong)(dong)(dong)(dong)(dong)杠連同轉軸(zhou)一同轉動(dong)(dong)(dong)(dong)(dong)，使(shi)凸輪(lun)(lun)(lun)推(tui)動(dong)(dong)(dong)(dong)(dong)撞塊(kuai)，當(dang)(dang)撞塊(kuai)碰壓到(dao)一定位(wei)置時(shi)(shi)，推(tui)動(dong)(dong)(dong)(dong)(dong)微動(dong)(dong)(dong)(dong)(dong)開(kai)(kai)關快速動(dong)(dong)(dong)(dong)(dong)作。當(dang)(dang)滾(gun)(gun)輪(lun)(lun)(lun)上(shang)的(de)(de)擋(dang)鐵(tie)移開(kai)(kai)后，復位(wei)彈(dan)簧(huang)就使(shi)行(xing)(xing)程(cheng)開(kai)(kai)關復位(wei)。這種是(shi)單輪(lun)(lun)(lun)自動(dong)(dong)(dong)(dong)(dong)恢復式(shi)行(xing)(xing)程(cheng)開(kai)(kai)關。而雙輪(lun)(lun)(lun)旋轉式(shi)行(xing)(xing)程(cheng)開(kai)(kai)關不能自動(dong)(dong)(dong)(dong)(dong)復原(yuan)(yuan)，它是(shi)依靠(kao)運動(dong)(dong)(dong)(dong)(dong)機械反向移動(dong)(dong)(dong)(dong)(dong)時(shi)(shi)，擋(dang)鐵(tie)碰撞另一滾(gun)(gun)輪(lun)(lun)(lun)將其復原(yuan)(yuan)。

3、微動式行程開關結構原理

由推桿(gan)(gan)(gan)、彈簧(huang)、壓(ya)縮彈簧(huang)、動(dong)(dong)斷觸(chu)(chu)(chu)點(dian)、動(dong)(dong)合(he)觸(chu)(chu)(chu)點(dian)組成，當推桿(gan)(gan)(gan)被壓(ya)下(xia)時(shi)(shi)(shi)，弓簧(huang)片(pian)發生變(bian)形(xing)，儲存能(neng)量并(bing)產(chan)生位移，當達到預(yu)定的臨界(jie)點(dian)時(shi)(shi)(shi)，彈簧(huang)片(pian)連同動(dong)(dong)觸(chu)(chu)(chu)點(dian)產(chan)生瞬時(shi)(shi)(shi)跳躍，從(cong)而(er)(er)導致電(dian)(dian)路的接通(tong)、分斷或轉(zhuan)換。同樣，減(jian)小操作(zuo)力時(shi)(shi)(shi)，彈簧(huang)片(pian)釋放能(neng)量并(bing)產(chan)生反向(xiang)位移，當通(tong)過另一臨界(jie)點(dian)時(shi)(shi)(shi)，彈簧(huang)片(pian)向(xiang)相(xiang)反方向(xiang)跳躍。采用瞬動(dong)(dong)機(ji)構(gou)可以(yi)使開關觸(chu)(chu)(chu)點(dian)的接觸(chu)(chu)(chu)速度(du)不受推桿(gan)(gan)(gan)壓(ya)下(xia)速度(du)的影(ying)響(xiang)，這(zhe)樣不僅(jin)可以(yi)減(jian)輕(qing)電(dian)(dian)弧對(dui)觸(chu)(chu)(chu)點(dian)的燒蝕，而(er)(er)且也能(neng)提高觸(chu)(chu)(chu)點(dian)動(dong)(dong)作(zuo)的準確(que)性。