【正文】
一名高效能人士不會到處為自己找借口,開脫責(zé)任;相反,無倫出現(xiàn)什么情況,他都會自覺主動地將自己的任務(wù)執(zhí)行到底。 that is ,a righthand driver goes with a righthand driven. In the design of crossedhelical gears, the minimum sliding velocity is obtained when the helix angle are equal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they pletely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angularvelocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A singleenveloping gearing is one in which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a doubleenveloping worm gearing. The important difference between the two is that area contact exists between the teeth of doubleenveloping gears while only line contact between those of singleenveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the plement of the worm helix angle, and the helix angle on the gear。為著這些用途就需要超載釋放保護(hù)離合器。所傳遞的扭矩關(guān)系到作用力,摩擦系數(shù)和離合器或制動器的幾何狀況?!拜S”這個詞包含著多種含義,例如心軸和主軸。輪齒可以鑄出,銑制或滾切加工。在交錯軸斜齒設(shè)計中,當(dāng)該齒的斜角相等時所產(chǎn)生滑移速度最小。直齒圓柱齒輪輪齒的初始接觸處是跨過整個齒面而伸展開來的線。此外,他們的嚴(yán)謹(jǐn)治學(xué)態(tài)度和忘我的工作精神值得我去學(xué)習(xí)。最后終于做完了有種如釋重負(fù)的感覺。 軸承的校核 1. 按手冊選擇C=61800N的軸承應(yīng)此軸承的基本額定靜載荷=38000N。選取軸的材料為45號鋼,調(diào)制處理。每個槽內(nèi)有一個鋼球,中間以保持架2保持鋼球的相對位置。其動力范圍為:Rn=9,Imax=1/Imin,P≤11 kw ,ε≤4% ,η=~ 。 綦江齒輪傳動有限公司主要為安凱、西沃、亞星奔馳、桂林大宇及廈門金龍等企業(yè)的7~12m高檔大、中型客車以及總質(zhì)量在14~50t 重型載貨車、鞍式牽引車、自卸車及各式專用車、特種車配套。由于目前在汽車上廣泛使用的自動變速技術(shù)是將液力變矩器和行星齒輪系組合的自動變速器,而他們的技術(shù)零部件數(shù)量過多,結(jié)構(gòu)復(fù)雜,保養(yǎng)和維護(hù)不便. 所以汽車行業(yè)早就開始研究其它新型變速技術(shù),無級變速(CVT)技術(shù)就是其中最有前景的一種?!稒C械無級變速器試驗方法》JB/T 751594與此同時,無級變速器專業(yè)協(xié)會、行業(yè)協(xié)會及情報網(wǎng)等組織相繼建立。 輸入軸的設(shè)計與計算 15167。廣泛應(yīng)用于紡織、輕工、機床、冶金、礦山、石油、化工、化纖、塑料、制藥、電子/造紙等領(lǐng)域,今年來已經(jīng)開始應(yīng)用于汽車的機械無級調(diào)速。直到20世紀(jì)50年代,尤其是70年代以后,一方面隨著先進(jìn)的冶煉和熱處理技術(shù),精密加工和數(shù)控機床以及牽引傳動理論與油品的出現(xiàn)和發(fā)展,解決了研制和生產(chǎn)無級變速器的限制因素;另一方面,隨著生產(chǎn)工藝流程實現(xiàn)機械化、自動化以及機械要改進(jìn)工作性能,都需要大量采用無級變速器。有人主張直接從國外引進(jìn)先進(jìn)的汽車自動變速箱技術(shù),不料國外所有相關(guān)公司都想直接從國外把汽車自動變速箱產(chǎn)品銷售到中國市場或者在中國建立獨資企業(yè)就地生產(chǎn)銷售產(chǎn)品,不愿與中國的企業(yè)合作開發(fā)生產(chǎn)獲取高額壟斷利潤。 畢業(yè)設(shè)計內(nèi)容和要求畢業(yè)設(shè)計類容:小功率機械無級變速器結(jié)構(gòu)的設(shè)計;比較和選擇合適的方案, 無級變速器變速器的結(jié)構(gòu)設(shè)計與計算;對關(guān)鍵部件進(jìn)行強度和壽命校核。如圖23為其特性曲線:圖 23 無級調(diào)速的特性曲線167。 應(yīng)此 加壓盤V行槽傾角 取= 加壓鋼球按經(jīng)驗公式取得 =驗算接觸強度均不足,故改用腰型滾子8個,取滾子軸向截面內(nèi)圓弧半徑=8cm,橫向中間截面半徑r=。 167。畢業(yè)設(shè)計總結(jié)通過此次畢業(yè)設(shè)計,我不僅把知識融會貫通,而且豐富了大腦,同時在查找資料的過程中也了解了許多課外知識,開拓了視野,認(rèn)識了將來電子的發(fā)展方向,使自己在專業(yè)知識方面和動手能力方面有了質(zhì)的飛躍。而且大大提高了動手的能力,使我充分體會到了在創(chuàng)造過程中探索的艱難和成功時的喜悅。所以我們對齒輪和軸的了解和認(rèn)識必須是多層次多方位的。斜齒輪使軸的軸承承受徑向和軸向力。蝸桿和蝸輪通常是用于向垂直相交軸之間的傳動提供大的角速度減速比。直齒錐齒輪易于設(shè)計且制造簡單,如果他們安裝的精密而確定,在運轉(zhuǎn)中會產(chǎn)生良好效果。但決不意味著設(shè)計者要保證;它們是安全的,軸幾乎總是要進(jìn)行計算的,知道它們是處在可以接受的允許的極限以內(nèi)。各種各樣的離合器和制動器可作如下分類:1. 輪緣式內(nèi)膨脹制凍塊;2. 輪緣式外接觸制動塊;3. 條帶式;4. 盤型或軸向式;5. 圓錐型;6. 混合式。該內(nèi)軸件,在它的周邊加工了數(shù)個平面。:“成功就是目標(biāo)的達(dá)成,其他都是這句話的注釋。這兩種能力是:第一,能思想;第二,能按事情的重要程度來做事。要事第一創(chuàng)設(shè)遍及全美的事務(wù)公司的亨瑞。 in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads bee high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossedhelical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossedhelical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not remended for use in the transmission of power. There is on difference between a crossed helical gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand。有些裝置例如線性驅(qū)動裝置或電機操作螺桿驅(qū)動器必須運行到一定的限度然后停頓下來。在分析這些裝置的性能時,我們應(yīng)注意到作用力,傳遞的扭矩,散失的能量和溫升。因為單根軸可以承受靜壓力,變應(yīng)力和交變應(yīng)力,所有的應(yīng)力作用都是同時發(fā)生的。雖然錐齒輪通常制造成能構(gòu)成90度軸交角,但它們也可產(chǎn)生任何角度的軸交角。一對相嚙合的交錯軸斜齒輪通常具有同樣的齒向,即左旋主動齒輪跟右旋從動齒輪相嚙合。如果我展開這張紙,在血角刃邊上的每一個點就發(fā)生一漸開線曲線。在這段時間里,我從他們身上,不僅學(xué)到了許多的專業(yè)知識,更感受到了他工作中的兢兢業(yè)業(yè),生活中的平易近人的精神。 總之,不管學(xué)會的還是學(xué)不會的的確覺得困難比較多,真是萬事開頭難,不知道如何入手。167。2. 初步確定軸的最小軸徑先按公式初步估算軸的最小直徑。 加壓盤的設(shè)計與計算1. 鋼球式自動加壓裝置它由加壓盤4,加壓鋼球3,保持架2,調(diào)整墊圈7, 蝶形彈簧6和摩擦輪與加壓盤相對端面上各有的幾條均布的V行槽。傳動鋼球的支承軸8的兩端,嵌裝在殼體兩端蓋12和13的徑向弧行倒槽內(nèi),并穿過調(diào)速渦輪5的曲線槽;調(diào)速時,通過蝸桿6和蝸輪5轉(zhuǎn)動,由于曲線槽的作用使鋼球軸線的傾斜角發(fā)生變化,導(dǎo)致鋼球與兩錐輪的工作半徑改變,輸出軸轉(zhuǎn)速得到調(diào)節(jié)。這些企業(yè)大多數(shù)變速器產(chǎn)品針對的市場各有側(cè)重, 像陜西法士特在8t 以上重型車市場占有率達(dá)到40 %以上, 并且在15t 以上重卡市場占有絕對的優(yōu)勢, 擁有85 %以上的市場份額。 無級變速研究現(xiàn)狀 CVT技術(shù)的發(fā)展,已經(jīng)有了一百多年的歷史。經(jīng)過十幾年的發(fā)展,國外現(xiàn)有的幾種主要類型結(jié)構(gòu)的無級變速器,在國內(nèi)皆有相應(yīng)的專業(yè)生產(chǎn)廠及系列產(chǎn)品,年產(chǎn)量約10萬臺左右,初步滿足了生產(chǎn)發(fā)展的需要。 無級變速器分為機械無級變速器,液壓傳動無級變速器,電力傳動無級變速器三種,所以以下重點介紹機械無級變速器。 調(diào)速齒輪上變速曲線槽的設(shè)計與計算 14167。 機械無級變速器的發(fā)展概況 3167。 由于機械無級變速器絕大多數(shù)是依靠摩擦傳遞動力,故承受過載和沖擊的能力差,且不能滿足嚴(yán)格的傳動比要求。因此在這種形式下,機械無級變速器獲得迅速和廣泛的發(fā)展。《行星錐盤無級變速器》