【機(jī)械類畢業(yè)論文中英文對(duì)照文獻(xiàn)翻譯】汽車車身焊裝夾具的設(shè)計(jì)要點(diǎn)

【機(jī)械類畢業(yè)論文中英文對(duì)照文獻(xiàn)翻譯】汽車車身焊裝夾具的設(shè)計(jì)要點(diǎn),機(jī)械類畢業(yè)論文中英文對(duì)照文獻(xiàn)翻譯,機(jī)械類,畢業(yè)論文,中英文,對(duì)照,對(duì)比,比照,文獻(xiàn),翻譯,汽車,車身,夾具,設(shè)計(jì),要點(diǎn) 附 錄 (英文文獻(xiàn)及中英文對(duì)照) The designing features of automobile body welding fixture Auto body clamp is required for the amorphous body stamping required to locate and clamp, to form the body components, combined parts, sub-assembly and assembly, While taking advantage of suitable welding method to form their own welding pieces of the whole. Welding fixture welding process is a secondary device, but in the process of mass production car body, the device is essential. It not only can improve welding productivity, but also to ensure the dimensional accuracy of welding products and appearance requirements of the important devices. The assembly and welding fixtures there is no uniform specifications and standardization, are non-standard equipment. Design.and manufacturing process according to the structural characteristcs of the specific models, production conditions and the actual demand from the line of design and manufacturing. 1. asonable decomposition of auto body parts welded together to determine the type of fixture required. Two or more of the stamping process by the assembly and welding of components is obtained by welding together pieces of several related small welding welding large pieces of formed pieces, then welded together to form the following four parts: Around before welding parts, welding parts around the back, floor and roof welding parts welding parts, welding together four pieces of the final welding into vehicle cab assembly. Therefore, according to the cab assembly formation process of the correct welding pieces of reasonably divided, and on this basis, the corresponding pieces of welding fixture design. This will not only help ensure product quality, also can increase welding productivity. 2. Determine the level of automation of assembly and welding fixtures. Annual output depends on the level of automation and assembly and welding fixtures welders bit configuration. Production cycle time mainly by clamping action, the assembly time, welding time and handling time and other components. Among them, the jig fixture operating time depends on the degree of automation. To improve productivity, consider clamping fixture and release time to complete the action by the cylinder, and between station and station automation transport. But this increases the manufacturing cost of fixtures. Therefore, the design of fixtures to be able to reasonably balance the level of automation and welding fixtures contradiction between the manufacturing cost. 3. For large welding jigs, fixtures must first determine the design basis, with the same car body design basis. Fixture n the location of all the components are determined directly from the design basis, the ultimate guarantee to create a qualified welding tooling structure. According to a preliminary decision height operations fixture floor height, the height of the clamped position; Second, draw the assembly and welding parts diagram, it is included in the station in need of assembly and welding of stamping the solder joint shape and location requirements as the basis for setting fixture; The next step is a reasonable arrangement of fixture position, this must be clearly grasp the stamping of the space shape, composition relationships, assembly and welding sequence and the solder joint layout, rational design of fixture placement and general structure; overall design of the final draw sketches. 4. Rational choice of fixture position. As the car body shape complexity, poor rigidity, deformation, fixture positioning has been introduced on a large number of ways to enhance the rigidity of welded parts, reduce the welding deformation. Positioning of welding fixtures generally include positioning and side positioning of two kinds of holes. Positioning hole punching process to give priority to consider the positioning hole, the size and location of these holes is relatively accurate and reliable; Try to use under the procedures of mounting holes, as these holes the size of the margin of error will affect the next process of the assembly. Therefore, the design of fixtures with positioning holes not only to understand the stamping process, assembly process must also consider the key under the channel size. Large lection of positioning holes as the holes, so that pins can have sufficient strength, or easily broken pins. Stamping on the preferred shape to a reliable, stable surface as a positioning surface, positioned to do as much as possible the use of flat surfaces, but most of the space body stamping surface, which requires the fixture components of the work surface must be positioned with the corresponding surface of the car body consistent shape, so as to ensure the body in the process of assembly and welding shape. Positioning of parts with surface to guarantee a certain accuracy, adjust the position of positioning blocks are coarse to fine-tune more complex, this block can be added to fine-tune the positioning function, that is positioned to add a thin spacer block, and gasket thickness is that you can adjust the accuracy. In addition, the set should also be considered when positioning the welding position and the use of welding equipment, welding can not affect the final piece out, but also allows welding clamp or welding torch to reach the location. For the really influential to consider the use of pins and other pins can be active. 5. Properly designed clamping mechanism. When the stamping on the correct positioning of the fixture, in order to maintain the welding process in the assembly of the workpiece position and overcome the elastic deformation of the workpiece, usually requires a certain clamping body. With this device, you can make the workpiece and the bearing surface, workpiece and positioning the workpiece and the workpiece surface and tight fit between. For thickness below 1.2mm steel plate, each clamping point of the clamping force is generally in the range of 300 ~ 750N; For the 1.5 ~ 2.5mm between the stampings, each clamping point of the clamping force in the range of 500 ~ 3000N. To reduce the auxiliary time loading and unloading the workpiece, the clamping device should be fast and efficient installations and multi-point linkage institutions. For sheet metal parts, the clamping force acting on the bearing surface point should be only a good piece of rigid role allowed a few points of support in the plane formed in order to avoid bending or clamping force from the workpiece positioning reference. Also designed to prevent the clamping mechanism to open the clamping grip hand. 6. Other design elements. As the stamping quality checks are sampling, prone to problems. If possible, add in some welding fixture on some auxiliary devices, check the stamping play the role of critical dimensions. In addition, assembly and welding fixture structure should be easy to operate, saving, security and easy handling characteristics of the workpiece. 汽車車身焊裝夾具的設(shè)計(jì)要點(diǎn) 汽車車身夾具是用來把所需車身沖壓件按要求定形、定位并夾緊，組合成車身組件、合件、分總成及總成，同時(shí)利用合適的焊接方法使其形成各自焊合件整體。焊接夾具屬于焊接工藝過程的輔助裝置，但在汽車車身大批量生產(chǎn)過程中，該裝置是必不可少的。它不僅可以提高焊接生產(chǎn)率，而且也是保證焊接產(chǎn)品的尺寸精度及外觀要求的重要裝置。而裝焊夾具沒有統(tǒng)一規(guī)格和標(biāo)準(zhǔn)化，屬于非標(biāo)準(zhǔn)設(shè)計(jì)和制造的工藝裝備，要根據(jù)具體車型的結(jié)構(gòu)特點(diǎn)、生產(chǎn)條件和實(shí)際需求來自行設(shè)計(jì)與制造。 1、合理分解汽車車身焊合件，確定所需夾具的種類。兩種或兩種以上的沖壓件經(jīng)裝焊工序后得到的部件即為焊合件，幾種相關(guān)的小焊合件組成大的焊合件，再形成以下四種焊合件：前圍焊合件、后側(cè)圍焊合件、地板焊合件以及頂蓋焊合件，這四種焊合件最終組焊成了汽車駕駛室總成。因此，要根據(jù)上述駕駛室總成形成過程進(jìn)行各種焊合件正確合理地分割，并在此基礎(chǔ)上進(jìn)行相應(yīng)焊合件夾具的設(shè)計(jì)。這樣，不僅有利于保證產(chǎn)品質(zhì)量，還可以提高焊接生產(chǎn)率。 2、確定裝焊夾具自動(dòng)化程度的高低。年產(chǎn)量決定于裝焊夾具的自動(dòng)化水平及焊接工位的配置。生產(chǎn)節(jié)拍主要由夾具動(dòng)作時(shí)間、裝配時(shí)間、焊接時(shí)間以及搬運(yùn)時(shí)間等組成。其中，夾具動(dòng)作時(shí)間主要取決于夾具的自動(dòng)化程度。為提高生產(chǎn)率，可以考慮夾具的夾緊和松開動(dòng)作由汽缸一次性完成，且工位和工位之間采用自動(dòng)化運(yùn)輸。但這就提高了夾具的制造成本。因此，設(shè)計(jì)夾具要能合理地平衡焊接夾具的自動(dòng)化水平及制造成本之間的矛盾。 3、對(duì)于大型焊裝夾具，首先必須確定夾具的設(shè)計(jì)基準(zhǔn)，它與汽車車身的設(shè)計(jì)基準(zhǔn)一致。夾具上全部元件的位置都是直接根據(jù)設(shè)計(jì)基準(zhǔn)確定的，最終保證制造出合格的焊接工裝結(jié)構(gòu)。根據(jù)作業(yè)高度可初步?jīng)Q定夾具底板的高度，即夾具固定位置的高度；其次繪制出裝焊工件圖，它包括在此工位上需要裝焊的沖壓件外形以及要求的焊點(diǎn)位置，以此作為夾具設(shè)置的基礎(chǔ)；下一步是夾具位置的合理布置，為此必須清楚地把握沖壓件的空間形狀、組合關(guān)系、裝焊順序以及焊點(diǎn)布置，合理設(shè)計(jì)夾具的安放位置和大致結(jié)構(gòu)；最后繪出總體方案設(shè)計(jì)草圖。 4、合理地選擇夾具的定位。由于汽車車身形狀復(fù)雜、剛性差、易變形，夾具定位上大量采用過定位方式，以增強(qiáng)焊接件剛性，減少焊接變形。焊接夾具的定位一般包括孔定位和面定位兩種?？锥ㄎ粫r(shí)要優(yōu)先考慮用沖壓工序的定位孔，這些孔的尺寸和位置相對(duì)準(zhǔn)確可靠；盡量用下道工序的裝配孔，因?yàn)檫@些孔的尺寸有誤差會(huì)影響下道工序的裝配。因此，設(shè)計(jì)夾具用孔定位時(shí)不僅要了解沖壓工序，還要考慮下道裝配工序的關(guān)鍵尺寸。定位孔盡可能選用較大的孔，這樣定位銷可以有足夠的強(qiáng)度，否則定位銷容易折斷。要優(yōu)選沖壓件上形狀可靠、穩(wěn)定的面作為定位面，盡可能地采用平面做定位面，但車身沖壓件大多為空間曲面，這就要求夾具定位元件的工作表面必須與車身上相應(yīng)的定位表面形狀保持一致，這樣才能在裝焊過程中保證車身的形狀。用面定位的部件要保證一定精度，調(diào)整定位塊的位置屬于粗調(diào)，要精確調(diào)節(jié)較為復(fù)雜，為此可以在定位塊上增加細(xì)調(diào)功能，即在定位塊上增加很薄的墊片，而墊片的厚度就是可以調(diào)整的精度。另外，設(shè)置定位時(shí)還要考慮焊接位置和所用焊接設(shè)備，既不能影響最終焊合件的取出，也可以讓焊鉗或者焊槍到達(dá)焊接位置。對(duì)于確實(shí)有影響的定位銷等要考慮采用可以活動(dòng)的定位銷。 5、正確設(shè)計(jì)夾緊機(jī)構(gòu)。當(dāng)沖壓件在夾具上正確定位后，為保持焊接過程中各工件的裝配位置以及克服工件的彈性變形，通常需要一定的夾緊機(jī)構(gòu)。利用該裝置，可以使工件和支承面、工件和定位面以及工件和工件之間緊密貼合。對(duì)于1.2mm厚度以下的鋼板，每個(gè)夾緊點(diǎn)的夾緊力一般在300~750N 范圍內(nèi)；對(duì)于1.5~2.5mm之間的沖壓件，每個(gè)夾緊點(diǎn)的夾緊力在500~3000N 范圍內(nèi)。為減少裝卸工件的輔助時(shí)間，夾緊裝置應(yīng)采用高效快速裝置和多點(diǎn)聯(lián)動(dòng)機(jī)構(gòu)。對(duì)于薄板沖壓件，夾緊力作用點(diǎn)應(yīng)作用在支承面上，只有對(duì)剛性很好的工件才允許作用在幾個(gè)支承點(diǎn)所組成的平面內(nèi)，以免夾緊力使工件彎曲或脫離定位基準(zhǔn)。另外設(shè)計(jì)時(shí)要防止在夾緊機(jī)構(gòu)由夾緊到打開時(shí)夾住手。 6、其它設(shè)計(jì)要點(diǎn)。由于沖壓件質(zhì)量檢查屬于抽檢，容易出現(xiàn)問題。如果可能，可以在有些焊接夾具上增加一些輔助裝置，起到檢查沖壓件關(guān)鍵尺寸的作用。另外，裝焊夾具結(jié)構(gòu)應(yīng)具有操作方便、省力、安全以及工件裝卸方便等特點(diǎn)。 6