外文翻譯--注射模成型零件工作尺寸計算方法分

外文翻譯 of of of of of in of by in of by an by of in of of is as or of , or of of or in of of of is as of in or of of is to of As to 1 in of at of of of ) z0 ls+3/4) ) z0 hs+2/3) 0z 1 of to of a b c he of +±（） in cp of Ä z of a to of to is it of to in to be 1 to of on of to of of by of It is in in 1 1 ) as by sz of is it () , of is it it to be 5 of to to is it (15 , ) , of of to ts . 020. 05it T3 T6 as In of be it to in to of at of is it to at of of at of of to is it of of to On as to is it of of of of to to on of of in so to in of of of 2 in In in to of a Lm is of of of ¦¤ in to ¦Ä, in to a 2 of of . is of so as to is it to on of of of a of of as （ of it to in （ +） of （ +） is it of on a to be is in to of + + is it Ä of to =+D) of it to in (s+c (7) to by to of of is of of a at to on or to as of or of it is to in in t at is it is it to to a as as it is if is to a is is it is it is it to to go on to of of to in in to of a Lm is of in to D is in to a 3 of of . 2. t is 3 of a of of is lm=+) of lm=+1+ of (1+ (8) is it of on a to be is in to of z+ (9) D=(z+ (10) to by to as of of is of of of is at to on or to it is to it is to of as is or on a of of it of in t at is it is it to to is it is it of of to to as as is is it is it to go on to to a of in of of or be is in of it it to be it in on to at t of 4 of of of an be of a of 4 he on a of s+1+on m=(1+ (11) 4 (is in to of (12) To is of on at in of , of at in 5 of hm=z=(1+z on (1+z (13) 5 of of an in in 5, is in of at is in to ) of (14) or of m= (15) It as (z/2)+ (16) Dj it to as j at 0" 6 1%, 0. 6% of 6 to of 7 8 " 7 of o of c of at z/2, it it is ig.s to by of 16 of 780+0. 1956. 370+0. 10mm is it to go as at c)(1=( =16 c)(1=( =6 It of of of of t be to is 6 a of 490+0. 1024. 140+0. 08mm is (1=5×( =6 (1=4×( =4 It of a of of of t be to To it is of is c of At z/2, of 36 to to 8 3060mm 6. 14060mm is z+(1=×( =he is is z+(1=×( =c)(1=(1 =6 校核證明該公式所確定的型腔徑向尺寸不能滿足設計要求。同理對模具型腔深度尺寸 則有 (1=5×(1 =6 (1=4×(1 =4 校核證明該公式所確定的型腔深度尺寸不能滿足設計要求。 對于型芯來 說 ,當型芯制造時是以最小極限尺寸 ,磨損量達到極限磨損量即制造公差的 z/2 時 ,生產(chǎn)出的塑件的型芯最小 ,就有可能超差 ,現(xiàn)對如圖 8 所示按平均收縮率計算模具型芯徑向尺寸 則有 z+(1=×(1 = 36 z+(1=×(1 =16 校核證 明該公式所確定的型芯徑向尺寸不能滿足設計要求。 對型芯高度尺寸 行校核 ,則有 z+(1=×(1 =4 型芯高度尺寸校核合格。 z+(1=×(1 =8 型芯高度尺寸校核不合格。 從以上的計算分析可以看出 ,采用平均收縮率計算得到的計算結果 ,在收縮率變化范圍較大、成型塑件的尺寸較大的情況下出現(xiàn)模具成型尺寸的計算結果往往超差的 ,這種超差現(xiàn)象常常被設計者所忽略或者根本沒有意識到。這樣就會使所設計的模具不能滿足設計和使用要求。 現(xiàn)在用極限公差的方法對該塑件的模具成型尺寸進行設計計算 ,首先對各成型尺寸的公差進行確定 ,對于徑向尺寸 ,型芯和型腔都有 : D=(s+c< 則模具校核合格 ,能夠達到設計要求 ,由此可以確定 值。當選用收縮率波動過大的材料時 ,確定的 算值過小 ,機械加工難以達到設計要求時 ,就可以在設計 過程中及時更換塑件材料 ,選取和采用收縮率波動小的塑料原料來滿足高精度塑件的要求。 對于型芯高度尺寸和型腔深度尺寸 ,由于磨量可以忽略不計 ,它們都有 : D=(s+ 則模具校核合格 ,能夠達到設計要求 ,由此可以確定 設最大磨損量 得到如圖 9和圖 10所示的模具成型尺寸及公差圖。 圖 9極限公差計算模具型腔尺寸 圖 10極限公差計算模具型芯尺寸 現(xiàn)對圖 9 中各尺寸進行校核 ,可知塑件可能現(xiàn)的最大尺寸是否在允許的尺寸公差規(guī)定范圍內(nèi) ,徑向尺寸可由下式進行校核 : c)(1=(1 116 核尺寸合格。 c)(1=(1 =核尺寸合格。型腔深度尺寸可由下式進行校核 : =6 核尺寸合格。 =4 核尺寸合格。 同理 ,對圖 10 中模具型芯中的各尺寸進行校核 ,知塑件可能出現(xiàn)的最小極限尺寸也在允許的尺寸公差規(guī)定范圍之內(nèi)。 由此可見 ,在進行模具成型尺寸的設計計算過 程中 ,當塑件材料的收縮率波動較大 ,同時塑件的尺 寸中等或較大時 ,由收縮率波動引起的公差變化幅 度較大 ,采用平均收縮率計算得到的結果往往出現(xiàn)超差現(xiàn)象。因此 ,應采用最大、最小收縮率和極限公差分析所得到的成型尺寸的計算公式和校核公式進行尺寸的計算和校核 ,這樣就可以準確地對模具成型工作尺寸的公差進行確定 ,當 公差過小 ,加工困難時 ,可以更換材料 ,選取和采用收縮率波動小的塑料滿足高精度塑件的要求 ,保證在設計階段就能發(fā)現(xiàn)模具在成型尺寸方面的問題 ,減少模具的返修率。 參考文獻 : 1彭建聲 ,秦曉剛 M機械工 業(yè)出版社 ,2000. 2范德梁 M遼寧科學技術 出版社 ,1983. 3成都科技大學 M中國輕工 業(yè)出版社 ,1992. 4馬金駿 修訂本 )M中國科 學技術出版社 ,1994. 5楊世英 ,陳棟傳 冊 M機械工業(yè)出版社 ,1994