要實(shí)現(xiàn)電磁閥密封要求,首先要保證主要密封件的結(jié)a構(gòu)設(shè)計(jì)合理,加工容易保證。參考進(jìn)口減壓閥的工作原理,進(jìn)行了如下改進(jìn)設(shè)計(jì)。
費(fèi)斯托FESTO電磁閥閥桿的設(shè)計(jì)
FESTO進(jìn)口電磁閥的密封形式是利用閥桿兩端錐面,通過(guò)閥桿的移動(dòng)分別密封入口端和放氣口端。這種密封形式要求閥桿的加工精度很高,特別是閥桿兩端錐面的同軸度要求在0.01mm以內(nèi)。這兩錐面用一般數(shù)控機(jī)床加工必須經(jīng)過(guò)在兩次定位分別加工,錐面同軸度要求很難保證,因此進(jìn)口電磁閥在使用過(guò)程中性能很不穩(wěn)定,使用壽命較短,而國(guó)內(nèi)傳統(tǒng)電磁閥只能應(yīng)用于低壓工作范圍。
在電磁閥的設(shè)計(jì)當(dāng)中,通過(guò)改變閥桿結(jié)構(gòu)形式,將原來(lái)閥桿兩端錐面密封形式改為一側(cè)端面密封,另一側(cè)保持錐面密封。這樣錐面的同軸度和端面的垂直度和跳動(dòng)度用普通數(shù)控機(jī)床可以在一次定位中加工出來(lái),閥桿的設(shè)計(jì)精度就比較容易保證,同時(shí)降低了加工成本。圖3為閥桿改型設(shè)計(jì)簡(jiǎn)圖。
費(fèi)斯托FESTO電磁閥密封力的設(shè)計(jì)
在電磁閥設(shè)計(jì)中,引進(jìn)氣動(dòng)密封力概念,即通過(guò)改變進(jìn)氣口兩端面的橫截面積S1、S2,使截面S1>S2,在通入高壓氣體P0時(shí),作用在兩截面的氣體壓力分別是:
F′1=P0·S1
F′2=P0·S2
這樣,當(dāng)電磁閥閉合時(shí),由于兩截面均密封,在截面兩端形成壓力差F′1-F′2,產(chǎn)生氣動(dòng)密封。此時(shí)電磁閥閉合時(shí)的密封力由氣體密封力和彈簧力共同提供,既保證了電磁閥閉合時(shí)所需要的密封力,同時(shí)可以降低了彈簧的設(shè)計(jì)強(qiáng)度,延長(zhǎng)彈簧的使用壽命。
費(fèi)斯托FESTO電磁閥常用產(chǎn)品型號(hào)如下：
電磁閥MDH-5/2-D-1-FRC電磁閥MDH-5/2-D-1-FRC雙電控電磁閥JMDH-5/2-D-1C雙電控電磁閥JMDH-5/2-D-1C電磁閥MDH-5/3G-D-1C電磁閥MDH-5/3G-D-1C電磁閥MDH-5/3E-D-1C電磁閥MDH-5/3E-D-1C電磁閥MDH-5/2-D-3-FRC電磁閥MDH-5/2-D-3-FRC雙電控電磁閥JMDH-5/2-D-3C雙電控電磁閥JMDH-5/2-D-3C電磁閥MDH-5/3G-D-3C電磁閥MDH-5/3G-D-3C電磁閥MDH-5/3E-D-3C電磁閥MDH-5/3E-D-3C氣控閥VL-5/2-D-1-FRC雙氣控閥J-5/2-D-1C氣控閥VL-5/3G-D-1C氣控閥VL-5/3E-D-1C電磁閥MDH-5/2-D-1C電磁閥MDH-5/2-D-1C電磁閥MDH-5/2-D-1C雙電控電磁閥JMDH-5/2-D-1C雙電控電磁閥JMDH-5/2-D-1C雙電控電磁閥JMDH-5/2-D-1C氣控閥VL-5/2-D-2-FRC雙氣控閥J-5/2-D-2C氣控閥VL-5/3G-D-2C氣控閥VL-5/3E-D-2C電磁閥MDH-5/2-D-2C電磁閥MDH-5/2-D-2C電磁閥MDH-5/2-D-2C雙電控電磁閥JMDH-5/2-D-2C雙電控電磁閥JMDH-5/2-D-2C雙電控電磁閥JMDH-5/2-D-2C氣控閥VL-5/2-D-3-FRC雙氣控閥J-5/2-D-3C氣控閥VL-5/3G-D-3C氣控閥VL-5/3E-D-3C電磁閥MDH-5/2-D-3C電磁閥MDH-5/2-D-3C電磁閥MDH-5/2-D-3C雙電控電磁閥JMDH-5/2-D-3C雙電控電磁閥JMDH-5/2-D-3C雙電控電磁閥JMDH-5/2-D-3C雙氣控閥JD-5/2-D-1C氣控閥VL-5/3G-D-1C氣控閥VL-5/3E-D-1C氣控閥VL-5/3B-D-1C電磁閥LMD-5/2-D-1C電磁閥LMD-5/3G-D-1C電磁閥LMD-5/3E-D-1-C電磁閥LMD-5/3B-D-1C雙氣控閥JD-5/2-D-3C氣控閥VL-5/3G-D-3C氣控閥VL-5/3E-D-3C氣控閥VL-5/3B-D-3C電磁閥LMD-5/2-D-3C電磁閥LMD-5/3G-D-3C電磁閥LMD-5/3E-D-3-C電磁閥LMD-5/3B-D-3C電磁閥MD-5/2-D-1C電磁閥MD-5/2-D-1C雙電控電磁閥JMDD-5/2-D-1C雙電控電磁閥JMDD-5/2-D-1C電磁閥MD-5/3G-D-1C電磁閥MD-5/3G-D-1C電磁閥MD-5/3E-D-1C電磁閥MD-5/3E-D-1C電磁閥MD-5/3B-D-1C電磁閥MD-5/3B-D-1C電磁閥MD-5/2-D-3C電磁閥MD-5/2-D-3C雙電控電磁閥JMDD-5/2-D-3C雙電控電磁閥JMDD-5/2-D-3C電磁閥MD-5/3G-D-3C電磁閥MD-5/3G-D-3C電磁閥MD-5/3E-D-3C電磁閥MD-5/3E-D-3C電磁閥MD-5/3B-D-3C電磁閥MD-5/3B-D-3C氣控閥VLH-5/2-D-1-FRC雙氣控閥JH-5/2-D-1C氣控閥VLH-5/3G-D-1C氣控閥VLH-5/3E-D-1C氣控閥VLH-5/3B-D-1C氣控閥VLH-5/2-D-3-FRC雙氣控閥JH-5/2-D-3C氣控閥VLH-5/3G-D-3C氣控閥VLH-5/3E-D-3C氣控閥VLH-5/3B-D-3C電磁閥MDH-5/2-D-1-FR-SC雙電控電磁閥JMDH-5/2-D-1-SC電磁閥MDH-5/3B-D-1-SC電磁閥MDH-5/3E-D-1-SC電磁閥MDH-5/3G-D-1-SC電磁閥MDH-5/2-D-3-FR-SC雙電控電磁閥JMDH-5/2-D-3-SC電磁閥MDH-5/3B-D-3-SC電磁閥MDH-5/3E-D-3-SC電磁閥MDH-5/3G-D-3-SC電磁閥MDH-5/3G-D-1C電磁閥MDH-5/3G-D-1C電磁閥MDH-5/3G-D-1C電磁閥MDH-5/3E-D-1C電磁閥MDH-5/3E-D-1C電磁閥MDH-5/3E-D-1C電磁閥MDH-5/3G-D-2C電磁閥MDH-5/3G-D-2C電磁閥MDH-5/3G-D-2C電磁閥MDH-5/3E-D-2C電磁閥MDH-5/3E-D-2C電磁閥MDH-5/3E-D-2C電磁閥MDH-5/3G-D-3C電磁閥MDH-5/3G-D-3C電磁閥MDH-5/3G-D-3C電磁閥MDH-5/3E-D-3C電磁閥MDH-5/3E-D-3C電磁閥MDH-5/3E-D-3C
