為防止真空泵進水,可在(zai)抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)塞(sai)上(shang)面增加1個(ge)T形(xing)(xing)管(guan)(見圖(tu)1), T形(xing)(xing)管(guan)進氣(qi)口上(shang)接一(yi)段橡皮管(guan)和(he)1個(ge)夾子。抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)塞(sai)下(xia)面接1個(ge)單自(zi)動活(huo)(huo)塞(sai),活(huo)(huo)塞(sai)芯(xin)(xin)下(xia)端用線繩固定在(zai)1個(ge)釘(ding)有(you)小鐵釘(ding)的(de)木(mu)板(ban)上(shang),當抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)進水時如接觸(chu)木(mu)板(ban),木(mu)板(ban)即(ji)因(yin)液面浮力將活(huo)(huo)塞(sai)芯(xin)(xin)向上(shang)頂,使(shi)抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)和(he)真(zhen)(zhen)空(kong)泵(beng)之間正(zheng)常通(tong)路(lu)(lu)(lu)自(zi)動關(guan)閉(bi),真(zhen)(zhen)空(kong)泵(beng)形(xing)(xing)成盲端,停(ting)(ting)止向抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)抽(chou)(chou)氣(qi);抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)內的(de)水液因(yin)通(tong)路(lu)(lu)(lu)關(guan)閉(bi)而不能(neng)進人真(zhen)(zhen)空(kong)泵(beng)內。關(guan)閉(bi)開(kai)關(guan),停(ting)(ting)止真(zhen)(zhen)空(kong)泵(beng)運(yun)轉。松(song)開(kai)T形(xing)(xing)管(guan)上(shang)的(de)夾子,讓空(kong)氣(qi)進入,然(ran)后(hou)松(song)開(kai)抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)下(xia)口夾子,使(shi)瓶(ping)(ping)(ping)內液體(ti)排出,活(huo)(huo)塞(sai)芯(xin)(xin)因(yin)木(mu)板(ban)重(zhong)力而下(xia)落,抽(chou)(chou)氣(qi)瓶(ping)(ping)(ping)與真(zhen)(zhen)空(kong)泵(beng)之間又形(xing)(xing)成通(tong)路(lu)(lu)(lu),開(kai)啟開(kai)關(guan),真(zhen)(zhen)空(kong)泵(beng)重(zhong)新(xin)運(yun)轉,抽(chou)(chou)氣(qi)又正(zheng)常進行。采(cai)取這種改進裝置后(hou),避免水液進入真(zhen)(zhen)空(kong)泵(beng),節約了真(zhen)(zhen)空(kong)泵(beng)油(you),減(jian)少了每(mei)次(ci)放(fang)水和(he)換油(you)的(de)麻煩(fan)。