播種機堵塞報警器的工作原理簡介

播(bo)(bo)種機存在一點不足，就是在播(bo)(bo)種時(shi)，播(bo)(bo)種機中的小(xiao)(xiao)麥(mai)(mai)下落管(guan)(guan)道很(hen)容易(yi)被小(xiao)(xiao)麥(mai)(mai)堵塞，而(er)人(ren)(ren)們又一時(shi)很(hen)難發現，導致人(ren)(ren)機白走一趟，浪費世間的同時(shi)無形之(zhi)中也降低了工作效率(lv)。這款小(xiao)(xiao)麥(mai)(mai)播(bo)(bo)種顆粒堵塞報警(jing)器，它能夠實施(shi)(shi)監測管(guan)(guan)道中小(xiao)(xiao)麥(mai)(mai)的下落情況，管(guan)(guan)道一旦被堵塞，電(dian)路立即發出報警(jing)，從(cong)而(er)提(ti)醒人(ren)(ren)們及時(shi)采取(qu)措施(shi)(shi)進行處(chu)理。

一、電路原理

該報(bao)警(jing)電(dian)(dian)(dian)(dian)(dian)路(lu)如(ru)下(xia)圖(tu)所示(shi)，電(dian)(dian)(dian)(dian)(dian)路(lu)采取(qu)紅(hong)外線原(yuan)理，將管(guan)(guan)(guan)道(dao)(dao)中小(xiao)麥(mai)(mai)的(de)下(xia)落情況轉換成電(dian)(dian)(dian)(dian)(dian)信號來控制報(bao)警(jing)電(dian)(dian)(dian)(dian)(dian)路(lu)。安裝時(shi)，注意要將紅(hong)外發光管(guan)(guan)(guan)VD1和(he)(he)接收管(guan)(guan)(guan)VD2正(zheng)對著(zhu)裝于小(xiao)麥(mai)(mai)下(xia)落管(guan)(guan)(guan)道(dao)(dao)中，使(shi)(shi)VD1管(guan)(guan)(guan)發出的(de)紅(hong)外光正(zheng)好照射(she)在VD2管(guan)(guan)(guan)上(shang)，這(zhe)樣(yang)閉合電(dian)(dian)(dian)(dian)(dian)源開關，當(dang)小(xiao)麥(mai)(mai)顆粒(li)在管(guan)(guan)(guan)子內正(zheng)常(chang)下(xia)落時(shi)，紅(hong)外光便被小(xiao)麥(mai)(mai)顆粒(li)時(shi)斷時(shi)續的(de)遮擋，使(shi)(shi)得VD2管(guan)(guan)(guan)的(de)負極產生一系列連(lian)續的(de)負脈(mo)沖(chong)，并通(tong)過電(dian)(dian)(dian)(dian)(dian)容(rong)C1耦合到電(dian)(dian)(dian)(dian)(dian)容(rong)C2的(de)正(zheng)極，從(cong)而使(shi)(shi)電(dian)(dian)(dian)(dian)(dian)容(rong)C2沖(chong)不(bu)上(shang)電(dian)(dian)(dian)(dian)(dian)，VT1三(san)(san)極管(guan)(guan)(guan)基極電(dian)(dian)(dian)(dian)(dian)壓(ya)近似為(wei)零(ling)，使(shi)(shi)得時(shi)基電(dian)(dian)(dian)(dian)(dian)路(lu)555的(de)2腳為(wei)低電(dian)(dian)(dian)(dian)(dian)平，同(tong)時(shi)由(you)于三(san)(san)極管(guan)(guan)(guan)VT1的(de)作用，只要電(dian)(dian)(dian)(dian)(dian)容(rong)C2上(shang)的(de)電(dian)(dian)(dian)(dian)(dian)壓(ya)為(wei)零(ling)，那么電(dian)(dian)(dian)(dian)(dian)容(rong)C3也(ye)(ye)就不(bu)會(hui)充上(shang)電(dian)(dian)(dian)(dian)(dian)，否則三(san)(san)極管(guan)(guan)(guan)VT1導通(tong)，也(ye)(ye)會(hui)將其放電(dian)(dian)(dian)(dian)(dian)，這(zhe)樣(yang)時(shi)基電(dian)(dian)(dian)(dian)(dian)路(lu)555的(de)2腳和(he)(he)6腳都為(wei)低電(dian)(dian)(dian)(dian)(dian)平，其3腳輸出高電(dian)(dian)(dian)(dian)(dian)平，三(san)(san)極管(guan)(guan)(guan)VT2飽(bao)和(he)(he)導通(tong)，振蕩電(dian)(dian)(dian)(dian)(dian)路(lu)不(bu)起(qi)振，揚聲器不(bu)報(bao)警(jing)。

當管道一旦被堵住后，小麥顆粒將不再落下，從(cong)而使得VD1管發(fa)出的紅外現實(shi)中照射（或不照射）在VD2管上(shang)，這樣，C1正極(ji)的電(dian)平始(shi)終為(wei)高(gao)或低，成為(wei)一直流信號，它將不再通過電(dian)容(rong)C1到達三極(ji)管VT1基極(ji)，于(yu)是電(dian)容(rong)C2開始(shi)充(chong)電(dian)，緊(jin)接著(zhu)，C3也隨著(zhu)C2的充(chong)電(dian)而充(chong)電(dian)，很快，電(dian)容(rong)C2、C3上(shang)的電(dian)壓(ya)便到達555的反(fan)轉電(dian)壓(ya)，555的2腳和6腳變成高(gao)電(dian)平，555復位(wei)，3腳輸出低電(dian)平，三極(ji)管VT2截止，啟動振(zhen)蕩電(dian)路，從(cong)而使揚聲器發(fa)聲報警。

二、實物調試與安裝
按原理(li)圖連(lian)接(jie)好電(dian)路后(hou)(hou)，閉(bi)合電(dian)源開關k，先(xian)用手模擬(ni)小麥顆粒下落，即(ji)將(jiang)手放于VD1管(guan)與VD2管(guan)之間，做上下揮(hui)動(dong)，使照射在VD2管(guan)上的(de)紅(hong)外線時斷時通，這時，揚聲(sheng)器(qi)應該不會(hui)發聲(sheng)，若不然(ran)可適當調節電(dian)位(wei)器(qi)RP1使其靈(ling)敏度(du)達到最佳(jia)狀(zhuang)態，然(ran)后(hou)(hou)將(jiang)手停止揮(hui)動(dong)，模擬(ni)管(guan)道堵塞，此時揚聲(sheng)器(qi)便(bian)會(hui)發聲(sheng)報警(jing)。

安裝實物時，最關鍵的一點就是紅外線對管的安裝，務必將兩管正對安裝于小麥下落的管道中。在播種工作進行時，閉合開關k，然后就可以工作了。對于機動播種機，則可以在播種機的耬齒附近安裝一個壓控開關來代替開關k，這樣，只有當播種機從機動車的懸掛位置放到地面上時，報警器才開始工作，避免了手動控制的麻煩。