一、行程開關工作原理是什么
行(xing)程(cheng)開關(guan)是(shi)(shi)主令電器(qi)里的(de)(de)(de)一種,其(qi)動(dong)作(zuo)(zuo)原理和(he)按鈕沒有什么(me)差(cha)別(bie)(bie),主要區別(bie)(bie)是(shi)(shi):它(ta)不是(shi)(shi)用手進(jin)行(xing)按壓操(cao)作(zuo)(zuo)而是(shi)(shi)用機械設(she)備的(de)(de)(de)一些運動(dong)部件與它(ta)的(de)(de)(de)傳動(dong)部位發生碰(peng)撞,來促使(shi)行(xing)程(cheng)開關(guan)的(de)(de)(de)觸頭動(dong)作(zuo)(zuo)的(de)(de)(de)(常開觸點閉(bi)合,常閉(bi)觸點斷(duan)開),能夠達到分斷(duan)或者切換電路的(de)(de)(de)目的(de)(de)(de)。
行程開關(guan)工作時,利用內部的元件碰撞,達(da)到開啟電路或(huo)關(guan)閉電路的功能(neng)。正常情況下(xia),行程開關(guan)一旦開啟,便(bian)會(hui)給機(ji)械(xie)運動(dong)添(tian)加上一個(ge)運動(dong)的軌跡(ji),只要機(ji)械(xie)達(da)到設定(ding)的位(wei)置,便(bian)會(hui)自動(dong)停止(zhi)運轉,或(huo)是改變運動(dong)狀態,從而達(da)到開關(guan)的目的。
二、不同結構的行程開關原理
行程開(kai)(kai)關按結(jie)構分(fen)主要可(ke)分(fen)為三種,三種行程開(kai)(kai)關的(de)原理有所不同:
1、直動式行程開關結構原理
直動(dong)(dong)式行程開關由推桿、彈簧、動(dong)(dong)斷觸點和動(dong)(dong)合(he)觸點組成,工(gong)作時,由運動(dong)(dong)部件的撞(zhuang)塊碰撞(zhuang),當外界運動(dong)(dong)部件上的撞(zhuang)塊碰壓按鈕使(shi)其觸頭(tou)動(dong)(dong)作,當運動(dong)(dong)部件離開后(hou),在(zai)彈簧作用下,其觸頭(tou)自動(dong)(dong)復位(wei)。
2、滾輪式行程開關結構原理
滾(gun)(gun)動(dong)式行(xing)(xing)程(cheng)開(kai)關的(de)(de)結構比較復(fu)(fu)雜,由滾(gun)(gun)輪(lun)(lun)、上(shang)(shang)(shang)轉(zhuan)臂、彈簧、套架、滑輪(lun)(lun)、壓(ya)板、觸點和橫板組成;工作時(shi)(shi),當(dang)(dang)運動(dong)機械的(de)(de)擋(dang)鐵(tie)(撞(zhuang)(zhuang)塊)壓(ya)到行(xing)(xing)程(cheng)開(kai)關的(de)(de)滾(gun)(gun)輪(lun)(lun)上(shang)(shang)(shang)時(shi)(shi),傳動(dong)杠連同轉(zhuan)軸一(yi)同轉(zhuan)動(dong),使(shi)凸輪(lun)(lun)推(tui)動(dong)撞(zhuang)(zhuang)塊,當(dang)(dang)撞(zhuang)(zhuang)塊碰(peng)(peng)壓(ya)到一(yi)定位(wei)置時(shi)(shi),推(tui)動(dong)微動(dong)開(kai)關快速動(dong)作。當(dang)(dang)滾(gun)(gun)輪(lun)(lun)上(shang)(shang)(shang)的(de)(de)擋(dang)鐵(tie)移(yi)開(kai)后(hou),復(fu)(fu)位(wei)彈簧就使(shi)行(xing)(xing)程(cheng)開(kai)關復(fu)(fu)位(wei)。這種是(shi)單輪(lun)(lun)自動(dong)恢復(fu)(fu)式行(xing)(xing)程(cheng)開(kai)關。而(er)雙輪(lun)(lun)旋轉(zhuan)式行(xing)(xing)程(cheng)開(kai)關不能自動(dong)復(fu)(fu)原(yuan),它是(shi)依靠運動(dong)機械反向移(yi)動(dong)時(shi)(shi),擋(dang)鐵(tie)碰(peng)(peng)撞(zhuang)(zhuang)另一(yi)滾(gun)(gun)輪(lun)(lun)將其復(fu)(fu)原(yuan)。
3、微動式行程開關結構原理
由(you)推桿、彈(dan)(dan)簧(huang)(huang)(huang)、壓縮彈(dan)(dan)簧(huang)(huang)(huang)、動(dong)(dong)(dong)斷觸點(dian)(dian)(dian)(dian)、動(dong)(dong)(dong)合觸點(dian)(dian)(dian)(dian)組(zu)成,當(dang)推桿被(bei)壓下時,弓簧(huang)(huang)(huang)片發生變形,儲存(cun)能量(liang)并產生位移(yi),當(dang)達到預定的臨界點(dian)(dian)(dian)(dian)時,彈(dan)(dan)簧(huang)(huang)(huang)片連同動(dong)(dong)(dong)觸點(dian)(dian)(dian)(dian)產生瞬時跳躍,從(cong)而導致(zhi)電路的接通、分斷或(huo)轉換(huan)。同樣,減小操作(zuo)力時,彈(dan)(dan)簧(huang)(huang)(huang)片釋放能量(liang)并產生反(fan)向(xiang)位移(yi),當(dang)通過另一臨界點(dian)(dian)(dian)(dian)時,彈(dan)(dan)簧(huang)(huang)(huang)片向(xiang)相反(fan)方向(xiang)跳躍。采用瞬動(dong)(dong)(dong)機構可以使開關觸點(dian)(dian)(dian)(dian)的接觸速度不受推桿壓下速度的影響(xiang),這樣不僅可以減輕電弧(hu)對觸點(dian)(dian)(dian)(dian)的燒蝕,而且也能提(ti)高(gao)觸點(dian)(dian)(dian)(dian)動(dong)(dong)(dong)作(zuo)的準確(que)性。