機(jī)構(gòu)設(shè)計(jì)外文翻譯-其他專業(yè)-資料下載頁
【導(dǎo)讀】們?cè)谶\(yùn)動(dòng)時(shí)彼此之間應(yīng)該具有確定的相對(duì)運(yùn)動(dòng)。打字機(jī)、機(jī)械式玩具、紡織機(jī)等等。一參考構(gòu)件產(chǎn)生所需要的相對(duì)運(yùn)動(dòng)。機(jī)構(gòu)的運(yùn)動(dòng)設(shè)計(jì)通常是設(shè)計(jì)一臺(tái)完整的機(jī)。在考慮力的作用時(shí)，應(yīng)該考慮動(dòng)力學(xué)、軸承載荷、應(yīng)力、潤滑等。在所考慮的問題的范圍擴(kuò)大之后，機(jī)構(gòu)設(shè)計(jì)就變成了機(jī)器設(shè)計(jì)。齒輪機(jī)構(gòu)在這種機(jī)構(gòu)中，各轉(zhuǎn)軸之間的運(yùn)動(dòng)由相互嚙合的齒輪來傳遞。動(dòng)件實(shí)現(xiàn)輸出運(yùn)動(dòng)時(shí)輸入運(yùn)動(dòng)的指定函數(shù)這一功能。剛體導(dǎo)向機(jī)構(gòu)用來引導(dǎo)一個(gè)剛體，使其通過空間一系列預(yù)定。構(gòu)有共同之處，然而，可以根據(jù)其構(gòu)件的運(yùn)動(dòng)特點(diǎn)來確定分類準(zhǔn)則。個(gè)視圖上表示出運(yùn)動(dòng)軌跡。此外，選擇過程應(yīng)該是一對(duì)。被利用的數(shù)量可能會(huì)減少。材料選用不當(dāng)造成的產(chǎn)品責(zé)任訴訟，已經(jīng)產(chǎn)生了深刻的影響。通常會(huì)促使人們對(duì)被加工材料進(jìn)行重新評(píng)價(jià)。料選擇工作，可以避免大多數(shù)的這種材料更換情況。大部分的產(chǎn)品失效和產(chǎn)品責(zé)任事故案件是由于在選用新材料作為替。代材料之前，沒有真正了解它們的長期使用性能而引起的。
【正文】 by , existing equipment, and that they are readily available in the needed quantities. As manufacturing progresses , it is inevitable that situations will arise that may require modifications of the materials being used. Experience may reveal that substitution of cheaper materials can be made .In most cases, however, changes are much more costly to make after manufacturing is in progress than before it starts. Good selection during the productiondesign phase will eliminate the necessity for this type of change . The more mon type of change that occurs after manufacturing starts is the result of the availability of new materials. These , of course , present possibilities for cost reduction and improved performance . However, new materials must be evaluate very carefully to make sure that all their characteristics are well established. One should always remember that it is indeed rare that as much is known about the properties and reliability of a new material as about those of an existing one. A large properties of product failure and product – liability cases have resulted from new materials being substituted before their longterm properties were really known . Product liability actions have made it imperative that designers and panies employ the very best procedures in selecting materials. The five most mon faults in material selection have been (a) failure to know and use the latest and best information available about the 外文 原文 63 materials utilized。 (b) failure to foresee, and take into account the reasonable uses for the product (where possible ,the designer is further advised to foresee and account for misuse of the product, as there have been many product liability cases in recent years where the claimant ,injured during misuse of the product ,has sued the manufacturer and won) 。 (c) the use of materials about which there was insufficient or uncertain data ,particularly as to its longterm properties。 (d) inadequate, and unverified, quality control procedures。 and (e) material selection made by people who are pletely unqualified to do so. An examination of the faults above will lead one to conclude that there is no good reason why they should exist .Consideration of them provides guidance as to how they can be eliminated. While following the very best methods in material selection may not eliminated all productliability claims, the use of proper procedures by designers and industries can greatly reduce their numbers. From the previous discussion, it is apparent that those who select materials should have a broad ,basic understanding of nature and properties of materials and their processing.
鄂ICP備17016276號(hào)-1