機(jī)械外文翻譯--連桿，內(nèi)燃機(jī)-免費(fèi)閱讀
【正文】 typically there is a pinhole bored through the bearing and the big end of the con rod so that pressurized lubricating motor oil squirts out onto the thrust side of the cylinder wall to lubricate the travel of the pistons and piston rings. The con rod is under tremendous stress from the reciprocating load represented by the piston, actually stretching and relaxing with every rotation, and the load increases rapidly with increasing engine speed. Failure of a connecting rod, usually called throwing a rod is one of the most mon causes of catastrophic engine failure in cars, frequently putting the broken rod through the side of the crankcase and thereby rendering the engine irreparable。裝有刀頭的鏜桿是一個懸臂梁，必須有非常高的剛度。 鏜床（類似于銑床，如經(jīng)典的范諾曼型）擁有多種尺寸和類型。這種曲柄連桿機(jī)構(gòu)可以減小膨脹行程中活塞與氣缸壁間的最大側(cè)壓力，使活塞在膨脹行程與壓縮 行程時作用在氣缸壁兩側(cè)的側(cè)壓力大小比較均勻。一個連桿在大端處一分為二，另一個變薄以與這個叉狀連桿相配。 最簡單的解決辦法是使用簡單的連桿，這種最簡單的方法通常用于汽車引擎。這確保了重新裝配后，軸瓦能與連桿精確地配合，而傳統(tǒng)加工方法制造的連桿與軸瓦，只 有當(dāng)兩者的接觸面表面的表面粗糙度都很小時才能達(dá)到較小的誤差。這是因為汽車零部件的生產(chǎn)中要使用一個比較大的安全系 數(shù)，同時往往還使用更系統(tǒng)的質(zhì)量控制體系。 內(nèi)燃機(jī) 在現(xiàn)代汽車內(nèi)燃發(fā)動機(jī)里，用于發(fā)動機(jī)的連桿通常由鋼制造，但也可以用鋁（目的是為了減輕重量和獲得在犧牲耐久度的條件下吸收強(qiáng)沖擊的能力）或鈦（目的是為了在需要支持力時提供一種既輕又有足夠強(qiáng)度的組合）來制造高性能發(fā)動機(jī)的連桿，或使用鑄鐵，如制 造摩托車連桿時就使用鑄件?！肚擅畹臋C(jī)械裝置知識》一書這樣寫道：“連桿發(fā)明于 1174 年至 1200 年的某個時候，當(dāng)一個名為阿拉 賈扎里的穆斯林 發(fā)明家、工程師和工匠，制造了 5 個機(jī)器來為土耳其阿爾圖格王朝的一位國王泵水 —— 這些機(jī)器的其中之一就使用了連桿。 連桿承受著巨大的壓力，這些壓力來自于由活塞產(chǎn)生的循環(huán)載荷 ，而事實上這些壓力來自于每次旋轉(zhuǎn)時的拉伸與松弛，以及隨發(fā)動機(jī)轉(zhuǎn)速增大而急劇增大的載荷。無論是連桿還是與其相配合的軸瓦，通常都會在發(fā)動機(jī)缸體上刻上相應(yīng)的型號。相反，較短的 連桿（或較小壓縮行程的活塞），會導(dǎo)致氣缸加速地磨損。對于確定設(shè)計的 V 形引擎，一對對置的氣缸使用一對主 /從動連桿。這種型式的曲柄連桿機(jī)構(gòu)在內(nèi)燃機(jī)中應(yīng)用最為廣泛。 鏜削有時也用于孔的加工。首先，大的長徑比是不希望的，因為這樣會使刀具變形。鍛造可對從不足 1 千克到 170 噸的工件進(jìn)行加工。 thus, for a given cylinder block longer stroke, giving greater engine displacement and power, requires a shorter connecting rod (or a piston with smaller pression height), resulting in accelerated cylinder wear. Compound rods Manycylinder multibank engines such as a V12 layout have little space available for that many connecting rod journals on a limited length of crankshaft. This is a difficult promise to solve and its consequence has often led to engines being regarded as failures. The simplest solution, almost universal in road car engines, is to use simple rods. This requires the rod bearings to be narrower, increasing bearing load and the risk of failure in a highperformance engine. This also means the opposing cylinders are not exactly in line with each other. In certain types of engine, the master rod carries one or more ring pins to which are bolted the much smaller big ends of slave rods on other cylinders. Radial engines typically have a master rod for one cylinder and slave rods for all the other cylinders in the same bank. Certain designs of V engines use a master/slave rod for each pair of opposite cylinders. A drawback of this is that the stroke of the subsidiary rod is slightly shorter than the master, which increases vibration in a vee engine. The usual solution for highperformance aeroengines is a forked connecting rod. One rod is split in two at the big end and th
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