机械毕业设计英文外文翻译354汽车车身焊装夹具的设计要点
汽车车身焊装夹具设计概述
汽车车身焊装夹具设计概述1. 引言1.1 汽车车身焊装夹具设计概述汽车车身焊装夹具设计在汽车生产中起着至关重要的作用，它直接影响着汽车的质量和生产效率。
夹具设计的好坏不仅关系到焊装工艺的精准度和稳定性，也直接影响了车身焊装的质量和成本。
夹具设计的重要性夹具设计是汽车制造中的关键环节，它决定了车身焊装过程中的定位、固定和连接方式。
一个良好的夹具设计可以确保焊接位置的准确性和稳定性，同时能够提高焊接的效率和质量。
夹具设计的原则包括结构简单、操作方便、稳定可靠、适应性强等。
在设计夹具时，需要考虑到生产工艺、工作效率、成本控制等因素，以确保夹具在实际生产中能够发挥最佳作用。
夹具设计包括夹具的结构设计、定位设计、固定设计等多个方面。
夹具的结构设计是夹具设计中最基本的内容，它直接影响着夹具的使用效果和寿命。
夹具设计的流程包括需求分析、方案设计、细化设计、制作调试等多个步骤。
在设计过程中，需要与生产、技术、质量等部门密切合作，确保夹具设计符合实际生产需求。
夹具设计的优化方法夹具设计的优化方法包括结构优化、材料优化、工艺优化等多个方面。
通过不断优化夹具设计，可以提高焊装生产效率，降低生产成本，提高焊装质量。
结论2. 正文2.1 夹具设计的重要性夹具设计在汽车车身焊装过程中起着至关重要的作用。
夹具是用来固定工件，保证工件在焊接过程中的位置和形状不变，从而保证焊接质量。
夹具设计的质量直接影响到焊接工艺参数的选择和焊接质量的稳定性，因此夹具设计的重要性不可忽视。
夹具设计能够提高生产效率。
通过合理设计夹具，可以缩短工人的操作时间，提高工作效率，减少生产成本，提高生产效率。
夹具设计还能够提高焊接质量。
通过精准的夹具设计，可以确保焊接工件的位置和形状稳定，避免焊接变形和缺陷，从而提高焊接质量。
夹具设计还能够保证产品的一致性。
通过统一的夹具设计标准，可以确保同一型号的车身焊装过程中使用的夹具保持一致，保证产品的一致性和标准化。
关于汽车车身焊装夹具设计探讨
关于汽车车身焊装夹具设计探讨摘要：在汽车车身前期设计中，焊装夹具设计是十分关键的内容，设计质量以及加工工艺能够直接影响汽车车身制造质量。
对此，本文首先对汽车车身焊装夹具的作用及组成进行介绍，然后对汽车焊装夹具设计原则以及具体的设计策略进行详细探究。
关键词：焊装；夹具；设计新时期，汽车已成为人们日常出行中的常用交通工具，通过加强汽车焊接质量控制，有利于提高汽车制造质量，促进汽车行业稳定发展。
汽车焊装夹具会直接影响汽车制造周期以及精度，因此，必须重点关注汽车焊装夹具设计。
一、汽车车身焊装夹具的作用及组成现如今，我国汽车使用量在世界范围内占据首位，国内汽车制造行业面临很多发展机遇和挑战，在汽车生产制造方面，车身质量管控至关重要，而不同车型的车身结构形式比较复杂，在具体的设计过程中构图难度大，在各类因素影响下容易发生变形，同时，车身尺寸还会对汽车结构装配质量以及效率产生较大影响，对此，需加强焊接装配工艺控制。
为了促进汽车车身焊接质量提升，应对焊装夹具进行优化设计，进而实现汽车车身流水线生产，尽量缩短焊接装配所需时间，同时通过提高夹具设计精度，还可保证汽车焊接装配质量和效率。
在汽车车身生产制造中，焊装夹具是十分重要的工具，通过快速定位工作元件，能够保证元件焊装的准确性。
在汽车制造中，在金属结构焊接方面，焊装夹具为十分关键的工具类型，在焊接工艺中可发挥夹持和固定的功能，确保汽车焊接工件的形状以及尺寸能够满足企业前期设计方案要求。
在具体的汽车车身焊接过程中，需充分发挥夹具的辅助作用，尽量减少焊接所需时间。
通常情况下，焊装夹具是由三个元件所组成的，即基础元件、符合标准元件以及外购元件[1]。
二、汽车焊装夹具设计原则在汽车焊装夹具设计中，对于整个设计过程，可分为四个环节，包括定位、夹紧、辅助元件以及夹具空间设计。
在具体的设计过程中，必须严格遵循六点定则，具体而言，需对六个方向自由度进行严格控制。
在对汽车车身六个方向自由度进行限定时，可联合应用孔定位法、面定位法等，确保零件定位准确性。
汽车焊接夹具设计外文文献翻译
汽车焊接夹具设计外文文献翻译(含：英文原文及中文译文)文献出处：Semjon Kim.Design of Automotive Welding Fixtures [J]. Computer-Aided Design, 2013, 3(12):21-32.英文原文Design of Automotive Welding FixturesSemjon Kim1 AbstractAccording to the design theory of car body welding fixture, the welding fixture and welding bus of each station are planned and designed. Then the fixture is modeled and assembled. The number and model of the fixture are determined and the accessibility is judged. Designed to meet the requirements of the welding fixture.Keywords: welded parts; foundation; clamping; position1 IntroductionAssembly and welding fixtures are closely related to the production of high-quality automotive equipment in automotive body assembly and welding lines. Welded fixtures are an important part of the welding process. Assembly and welding fixtures are not only the way to complete the assembly of parts in this process, but also as a test and calibration procedure on the production line to complete the task of testing welding accessories and welding quality. Therefore, the design and manufacture ofwelding fixtures directly affect the production capacity and product quality of the automobile in the welding process. Automotive welding fixtures are an important means of ensuring their manufacturing quality and shortening their manufacturing cycle. Therefore, it is indispensable to correctly understand the key points of welding fixture design, improve and increase the design means and design level of welding fixtures, and improve the adjustment and verification level of fixtures. It is also an auto manufacturing company in the fierce competition. The problem that must be solved to survive.The style of the car is different from that of the car. Therefore, the shape of the welding jig is very different. However, the design, manufacture, and adjustment are common and can be used for reference.2. Structural design of welding fixtureThe structure design of the welding fixture ensures that the clip has good operational convenience and reliable positioning of the fixture. Manufacturers of welding fixtures can also easily integrate adjustments to ensure that the surfaces of the various parts of the structure should allow enough room for adjustments to ensure three-dimensional adjustment. Of course, under the premise of ensuring the accuracy of the welding jig, the structure of the welding jig should be as simple as possible. The fixture design is usually the position of all components on the fixture is determined directly based on the design basis, and ultimately ensure thatthe qualified welding fixture structure is manufactured. According to the working height, the height of the fixture bottom plate can be preliminarily determined, that is, the height of the fixture fixing position. The welding fixture design must first consider the clamping method. There are two types, manual and pneumatic. Manual clamping is generally suitable for small parts, external parts, and small batches of workpieces. For large body parts, planning in the production line, automation High-demand welding fixtures should be pneumatically clamped. Automobile production is generally pneumatically clamped, and manual mass clamping can be used as auxiliary clamping. This can reduce costs accordingly. Some manual clamping products already have standard models and quantities, which can be purchased in the market when needed. For some devices, pneumatic clamping is specified, but if pneumatic clamping is used, the workpiece may be damaged. Therefore, it is possible to manually press the place first to provide a pneumatic clamping force to clamp the workpiece. This is manual-pneumatic. . The fixture clamping system is mounted on a large platform, all of which are fixed in this welding position to ensure that the welding conditions should meet the design dimensions of the workpiece coordinate system positioning fixture, which involves the benchmark.3. Benchmarks of assembly and welding fixtures and their chosen support surfaces3.1 Determination of design basisIn order to ensure that the three-dimensional coordinates of the automatic weldment system are consistent, all welding fixtures must have a common reference in the system. The benchmark is the fixture mounting platform. This is the X, Y coordinate, each specific component is fixed at the corresponding position on the platform, and has a corresponding height. Therefore, the Z coordinate should be coordinated, and a three-dimensional XYZ coordinate system is established. In order to facilitate the installation and measurement of the fixture, the mounting platform must have coordinates for reference. There are usually three types. The structure is as follows:3.1.1 Reference hole methodThere are four reference holes in the design of the installation platform, in which the two directions of the center coordinates of each hole and the coordinates of the four holes constitute two mutually perpendicular lines. This is the collection on the XY plane coordinate system. The establishment of this benchmark is relatively simple and easy to process, but the measurements and benchmarks used at the same time are accurate. Any shape is composed of spatial points. All geometric measurements can be attributed to measurements of spatial points. Accurate spatial coordinate acquisition is therefore the basis for assessing any geometric shape. Reference A coordinated direction formed by oneside near two datums.3.1.2 v-type detection methodIn this method, the mounting platform is divided into two 90-degree ranges. The lines of the two axes make up a plane-mounted platform. The plane is perpendicular to the platform. The surface forms of these two axis grooves XY plane coordinate system.3.1.3 Reference block methodReference Using the side block perpendicular to the 3D XYZ coordinate system, the base of a gage and 3 to 4 blocks can be mounted directly on the platform, or a bearing fixing fixture platform can be added, but the height of the reference plane must be used to control the height , must ensure the same direction. When manufacturing, it is more difficult to adjust the previous two methods of the block, but this kind of measurement is extremely convenient, especially using the CMM measurement. This method requires a relatively low surface mount platform for the reference block, so a larger sized mounting platform should use this method.Each fixture must have a fixed coordinate system. In this coordinate system, its supporting base coordinate dimensions should support the workpiece and the coordinates correspond to the same size. So the choice of bearing surface in the whole welding fixture system 3.2When the bearing surface is selected, the angle between the tangentplane and the mounting platform on the fixed surface of the welding test piece shall not be greater than 15 degrees. The inspection surface should be the same as the welded pipe fittings as much as possible for the convenience of flat surface treatment and adjustment. The surface structure of the bearing should be designed so that the module can be easily handled, and this number can be used for the numerical control of the bearing surface of the product. Of course, designing the vehicle body coordinate point is not necessarily suitable for the bearing surface, especially the NC fixture. This requires the support of the fixture to block the access point S, based on which the digital surface is established. This surface should be consistent with the supported surface. So at this time, it is easier and easier to manufacture the base point S, CNC machining, precision machining and assembly and debugging.3.2 Basic requirements for welding fixtureIn the process of automobile assembly and production, there are certain requirements for the fixture. First, according to the design of the automobile and the requirements of the welding process, the shape, size and precision of the fixture have reached the design requirements and technical requirements. This is a link that can not be ignored, and the first consideration in the design of welding fixture is considered. When assembling, the parts or parts of the assembly should be consistent with the position of the design drawings of the car and tighten with the fixture.At the same time, the position should be adjusted to ensure that the position of the assembly parts is clamped accurately so as to avoid the deformation or movement of the parts during the welding. Therefore, this puts forward higher requirements for welding jig. In order to ensure the smooth process of automobile welding and improve the production efficiency and economic benefit, the workers operate conveniently, reduce the strength of the welder's work, ensure the precision of the automobile assembly and improve the quality of the automobile production. Therefore, when the fixture design is designed, the design structure should be relatively simple, it has good operability, it is relatively easy to make and maintain, and the replacement of fixture parts is more convenient when the fixture parts are damaged, and the cost is relatively economical and reasonable. But the welding fixture must meet the construction technology requirements. When the fixture is welded, the structure of the fixture should be open so that the welding equipment is easy to close to the working position, which reduces the labor intensity of the workers and improves the production efficiency.4. Position the workpieceThe general position of the workpiece surface features is determined relative to the hole or the apparent positioning reference surface. It is commonly used as a locating pin assembly. It is divided into two parts: clamping positioning and fixed positioning. Taking into account thewelding position and all welding equipment, it is not possible to influence the removal of the final weld, but also to allow the welding clamp or torch to reach the welding position. For truly influential positioning pins and the like, consider using movable positioning pins. In order to facilitate the entry and exit of parts, telescopic positioning pins are available. The specific structure can be found in the manual. The installation of welding fixtures should be convenient for construction, and there should be enough space for assembly and welding. It must not affect the welding operation and the welder's observation, and it does not hinder the loading and unloading of the weldment. All positioning elements and clamping mechanisms should be kept at a proper distance from the solder joints or be placed under or on the surface of the weldment. The actuator of the clamping mechanism should be able to flex or index. According to the formation principle, the workpiece is clamped and positioned. Then open the fixture to remove the workpiece. Make sure the fixture does not interfere with opening and closing. In order to reduce the auxiliary time for loading and unloading workpieces, the clamping device should use high-efficiency and quick devices and multi-point linkage mechanisms. For thin-plate stampings, the point of application of the clamping force should act on the bearing surface. Only parts that are very rigid can be allowed to act in the plane formed by several bearing points so that the clamping force does not bend the workpiece or deviate from thepositioning reference. In addition, it must be designed so that it does not pinch the hand when the clamping mechanism is clamped to open.5. Work station mobilization of welding partsMost automotive solder fittings are soldered to complete in several processes. Therefore, it needs a transmission device. Usually the workpiece should avoid the interference of the welding fixture before transmission. The first step is to lift the workpiece. This requires the use of an elevator, a crane, a rack and pinion, etc. The racks and gears at this time Structure, their structural processing, connection is not as simple as the completion of the structure of the transmission between the usual connection structure of the station, there are several forms, such as gears, rack drive mechanism, transmission mechanism, rocker mechanism, due to the reciprocating motion, shake The transfer of the arm mechanism to the commissioning is better than the other one, so the common rocker arm transfer mechanism is generally used.6 ConclusionIn recent years, how to correctly and reasonably set the auxiliary positioning support for automotive welding fixtures is an extremely complicated system problem. Although we have accumulated some experience in this area, there is still much to be learned in this field. Learn and research to provide new theoretical support for continuous development and innovation in the field of welding fixture design. Withthe development of the Chinese automotive industry, more and more welding fixtures are needed. Although the principle of the fixture is very simple, the real design and manufacture of a high-quality welding fixture system is an extremely complicated project.中文译文汽车焊接夹具的设计Semjon Kim1摘要依据车体焊装线夹具设计理论, 对各工位焊接夹具及其焊装总线进行规划、设计, 之后进行夹具建模、装配, 插入焊钳确定其数量、型号及判断其可达性,最终设计出符合要求的焊接夹具。
机械加工毕业论文中英文资料外文翻译文献
毕业论文中英文资料外文翻译文献附录附录1：英文原文Selection of optimum tool geometry and cutting conditionsusing a surface roughness prediction model for end milling Abstract Influence of tool geometry on the quality of surface produced is well known and hence any attempt to assess the performance of end milling should include the tool geometry. In the present work, experimental studies have been conducted to see the effect of tool geometry (radial rake angle and nose radius) and cutting conditions (cutting speed and feed rate) on the machining performance during end milling of medium carbon steel. The first and second order mathematical models, in terms of machining parameters, were developed for surface roughness prediction using response surface methodology (RSM) on the basis of experimental results. The model selected for optimization has been validated with the Chi square test. The significance of these parameters on surface roughness has been established with analysis of variance. An attempt has also been made to optimize the surface roughness prediction model using genetic algorithms (GA). The GA program gives minimum values of surface roughness and their respective optimal conditions.1 IntroductionEnd milling is one of the most commonly used metal removal operations in industry because of its ability to remove material faster giving reasonably good surface quality. It is used in a variety of manufacturing industries including aerospace and automotive sectors, where quality is an important factor in the production of slots, pockets, precision moulds and dies. Greater attention is given to dimensional accuracy and surface roughness of products by the industry these days. Moreover, surface finish influences mechanical properties such as fatigue behaviour, wear, corrosion, lubrication and electrical conductivity. Thus, measuring and characterizing surface finish can be considered for predicting machining performance.Surface finish resulting from turning operations has traditionally received considerable research attention, where as that of machining processes using multipoint cutters, requires attention by researchers. As these processes involve large number of parameters, it would bedifficult to correlate surface finish with other parameters just by conducting experiments. Modelling helps to understand this kind of process better. Though some amount of work has been carried out to develop surface finish prediction models in the past, the effect of tool geometry has received little attention. However, the radial rake angle has a major affect on the power consumption apart from tangential and radial forces. It also influences chip curling and modifies chip flow direction. In addition to this, researchers [1] have also observed that the nose radius plays a significant role in affecting the surface finish. Therefore the development of a good model should involve the radial rake angle and nose radius along with other relevant factors.Establishment of efficient machining parameters has been a problem that has confronted manufacturing industries for nearly a century, and is still the subject of many studies. Obtaining optimum machining parameters is of great concern in manufacturing industries, where the economy of machining operation plays a key role in the competitive market. In material removal processes, an improper selection of cutting conditions cause surfaces with high roughness and dimensional errors, and it is even possible that dynamic phenomena due to auto excited vibrations may set in [2]. In view of the significant role that the milling operation plays in today’s manufacturing world, there is a need to optimize the machining parameters for this operation. So, an effort has been made in this paper to see the influence of tool geometry(radial rake angle and nose radius) and cutting conditions(cutting speed and feed rate) on the surface finish produced during end milling of medium carbon steel. The experimental results of this work will be used to relate cutting speed, feed rate, radial rake angle and nose radius with the machining response i.e. surface roughness by modelling. The mathematical models thus developed are further utilized to find the optimum process parameters using genetic algorithms.2 ReviewProcess modelling and optimization are two important issues in manufacturing. The manufacturing processes are characterized by a multiplicity of dynamically interacting process variables. Surface finish has been an important factor of machining in predicting performance of any machining operation. In order to develop and optimize a surface roughness model, it is essential to understand the current status of work in this area.Davis et al. [3] have investigated the cutting performance of five end mills having various helix angles. Cutting tests were performed on aluminium alloy L 65 for three milling processes (face, slot and side), in which cutting force, surface roughness and concavity of a machined plane surface were measured. The central composite design was used to decide on the number of experiments to be conducted. The cutting performance of the end mills was assessed usingvariance analysis. The affects of spindle speed, depth of cut and feed rate on the cutting force and surface roughness were studied. The investigation showed that end mills with left hand helix angles are generally less cost effective than those with right hand helix angles. There is no significant difference between up milling and down milling with regard tothe cutting force, although the difference between them regarding the surface roughness was large. Bayoumi et al.[4] have studied the affect of the tool rotation angle, feed rate and cutting speed on the mechanistic process parameters (pressure, friction parameter) for end milling operation with three commercially available workpiece materials, 11 L 17 free machining steel, 62- 35-3 free machining brass and 2024 aluminium using a single fluted HSS milling cutter. It has been found that pressure and friction act on the chip – tool interface decrease with the increase of feed rate and with the decrease of the flow angle, while the cutting speed has a negligible effect on some of the material dependent parameters. Process parameters are summarized into empirical equations as functions of feed rate and tool rotation angle for each work material. However, researchers have not taken into account the effects of cutting conditions and tool geometry simultaneously; besides these studies have not considered the optimization of the cutting process.As end milling is a process which involves a large number f parameters, combined influence of the significant parameters an only be obtained by modelling. Mansour and Abdallaet al. [5] have developed a surface roughness model for the end milling of EN32M (a semi-free cutting carbon case hardening steel with improved merchantability). The mathematical model has been developed in terms of cutting speed, feed rate and axial depth of cut. The affect of these parameters on the surface roughness has been carried out using response surface methodology (RSM). A first order equation covering the speed range of 30–35 m/min and a second order equation covering the speed range of 24–38 m/min were developed under dry machining conditions. Alauddin et al. [6] developed a surface roughness model using RSM for the end milling of 190 BHN steel. First and second order models were constructed along with contour graphs for the selection of the proper combination of cutting speed and feed to increase the metal removal rate without sacrificing surface quality. Hasmi et al. [7] also used the RSM model for assessing the influence of the workpiece material on the surface roughness of the machined surfaces. The model was developed for milling operation by conducting experiments on steel specimens. The expression shows, the relationship between the surface roughness and the various parameters; namely, the cutting speed, feed and depth of cut. The above models have not considered the affect of tool geometry on surface roughness.Since the turn of the century quite a large number of attempts have been made to find optimum values of machining parameters. Uses of many methods have been reported in the literature to solve optimization problems for machining parameters. Jain and Jain [8] have usedneural networks for modeling and optimizing the machining conditions. The results have been validated by comparing the optimized machining conditions obtained using genetic algorithms. Suresh et al. [9] have developed a surface roughness prediction model for turning mild steel using a response surface methodology to produce the factor affects of the individual process parameters. They have also optimized the turning process using the surface roughness prediction model as the objective function. Considering the above, an attempt has been made in this work to develop a surface roughness model with tool geometry and cutting conditions on the basis of experimental results and then optimize it for the selection of these parameters within the given constraints in the end milling operation.3 MethodologyIn this work, mathematical models have been developed using experimental results with the help of response surface methodolog y. The purpose of developing mathematical models relating the machining responses and their factors is to facilitate the optimization of the machining process. This mathematical model has been used as an objective function and the optimization was carried out with the help of genetic algorithms.3.1 Mathematical formulationResponse surface methodology(RSM) is a combination of mathematical and statistical techniques useful for modelling and analyzing the problems in which several independent variables influence a dependent variable or response. The mathematical models commonly used are represented by:where Y is the machining response, ϕ is the response function and S, f , α, r are milling variables and ∈is the error which is normally distributed about the observed response Y with zero mean.The relationship between surface roughness and other independent variables can be represented as follows，where C is a constant and a, b, c and d are exponents.To facilitate the determination of constants and exponents, this mathematical model will have to be linearized by performing a logarithmic transformation as follows:The constants and exponents C, a, b, c and d can be determined by the method of least squares. The first order linear model, developed from the above functional relationship using least squares method, can be represented as follows:where Y1 is the estimated response based on the first-order equation, Y is the measured surface roughness on a logarithmic scale, x0 = 1 (dummy variable), x1, x2, x3 and x4 are logarithmic transformations of cutting speed, feed rate, radial rake angle and nose radiusrespectively, ∈is the experimental error and b values are the estimates of corresponding parameters.The general second order polynomial response is as given below:where Y2 is the estimated response based on the second order equation. The parameters, i.e. b0, b1, b2, b3, b4, b12, b23, b14, etc. are to be estimated by the method of least squares. Validity of the selected model used for optimizing the process parameters has been tested with the help of statistical tests, such as F-test, chi square test, etc. [10].3.2 Optimization using genetic algorithmsMost of the researchers have used traditional optimization techniques for solving machining problems. The traditional methods of optimization and search do not fare well over a broad spectrum of problem domains. Traditional techniques are not efficient when the practical search space is too large. These algorithms are not robust. They are inclined to obtain a local optimal solution. Numerous constraints and number of passes make the machining optimization problem more complicated. So, it was decided to employ genetic algorithms as an optimization technique. GA come under the class of non-traditional search and optimization techniques. GA are different from traditional optimization techniques in the following ways:1.GA work with a coding of the parameter set, not the parameter themselves.2.GA search from a population of points and not a single point.3.GA use information of fitness function, not derivatives or other auxiliary knowledge.4.GA use probabilistic transition rules not deterministic rules.5.It is very likely that the expected GA solution will be the global solution.Genetic algorithms (GA) form a class of adaptive heuristics based on principles derived from the dynamics of natural population genetics. The searching process simulates the natural evaluation of biological creatures and turns out to be an intelligent exploitation of a random search. The mechanics of a GA is simple, involving copying of binary strings. Simplicity of operation and computational efficiency are the two main attractions of the genetic algorithmic approach. The computations are carried out in three stages to get a result in one generation or iteration. The three stages are reproduction, crossover and mutation.In order to use GA to solve any problem, the variable is typically encoded into a string (binary coding) or chromosome structure which represents a possible solution to the given problem. GA begin with a population of strings (individuals) created at random. The fitness of each individual string is evaluated with respect to the given objective function. Then this initial population is operated on by three main operators – reproduction cross over and mutation– to create, hopefully, a better population. Highly fit individuals or solutions are given theopportunity to reproduce by exchanging pieces of their genetic information, in the crossover procedure, with other highly fit individuals. This produces new “offspring” solutions, which share some characteristics taken from both the parents. Mutation is often applied after crossover by altering some genes (i.e. bits) in the offspring. The offspring can either replace the whole population (generational approach) or replace less fit individuals (steady state approach). This new population is further evaluated and tested for some termination criteria. The reproduction-cross over mutation- evaluation cycle is repeated until the termination criteria are met.4 Experimental detailsFor developing models on the basis of experimental data, careful planning of experimentation is essential. The factors considered for experimentation and analysis were cutting speed, feed rate, radial rake angle and nose radius.4.1 Experimental designThe design of experimentation has a major affect on the number of experiments needed. Therefore it is essential to have a well designed set of experiments. The range of values of each factor was set at three different levels, namely low, medium and high as shown in Table 1. Based on this, a total number of 81 experiments (full factorial design), each having a combination of different levels of factors, as shown in Table 2, were carried out.The variables were coded by taking into account the capacity and limiting cutting conditions of the milling machine. The coded values of variables, to be used in Eqs. 3 and 4, were obtained from the following transforming equations:where x1 is the coded value of cutting speed (S), x2 is the coded value of the feed rate ( f ), x3 is the coded value of radial rake angle(α) and x4 is the coded value of nose radius (r).4.2 ExperimentationA high precision ‘Rambaudi Rammatic 500’ CNC milling machine, with a vertical milling head, was used for experimentation. The control system is a CNC FIDIA-12 compact. The cutting tools, used for the experimentation, were solid coated carbide end mill cutters of different radial rake angles and nose radii (WIDIA: DIA20 X FL38 X OAL 102 MM). The tools are coated with TiAlN coating. The hardness, density and transverse rupture strength are 1570 HV 30, 14.5 gm/cm3 and 3800 N/mm2 respectively.AISI 1045 steel specimens of 100×75 mm and 20 mm thickness were used in the present study. All the specimens were annealed, by holding them at 850 ◦C for one hour and then cooling them in a furnace. The chemical analysis of specimens is presented in Table 3. Thehardness of the workpiece material is 170 BHN. All the experiments were carried out at a constant axial depth of cut of 20 mm and a radial depth of cut of 1 mm. The surface roughness (response) was measured with Talysurf-6 at a 0.8 mm cut-off value. An average of four measurements was used as a response value.5 Results and discussionThe influences of cutting speed, feed rate, radial rake angle and nose radius have been assessed by conducting experiments. The variation of machining response with respect to the variables was shown graphically in Fig. 1. It is seen from these figures that of the four dependent parameters, radial rake angle has definite influence on the roughness of the surface machined using an end mill cutter. It is felt that the prominent influence of radial rake angle on the surface generation could be due to the fact that any change in the radial rake angle changes the sharpness of the cutting edge on the periphery, i.e changes the contact length between the chip and workpiece surface. Also it is evident from the plots that as the radial rake angle changes from 4◦to 16◦, the surface roughness decreases and then increases. Therefore, it may be concluded here that the radial rake angle in the range of 4◦to 10◦would give a better surface finish. Figure 1 also shows that the surface roughness decreases first and then increases with the increase in the nose radius. This shows that there is a scope for finding the optimum value of the radial rake angle and nose radius for obtaining the best possible quality of the surface. It was also found that the surface roughness decreases with an increase in cutting speed and increases as feed rate increases. It could also be observed that the surface roughness was a minimum at the 250 m/min speed, 200 mm/min feed rate, 10◦radial rake angle and 0.8 mm nose radius. In order to understand the process better, the experimental results can be used to develop mathematical models using RSM. In this work, a commercially available mathematical software package (MATLAB) was used for the computation of the regression of constants and exponents.5.1 The roughness modelUsing experimental results, empirical equations have been obtained to estimate surface roughness with the significant parameters considered for the experimentation i.e. cutting speed, feed rate, radial rake angle and nose radius. The first order model obtained from the above functional relationship using the RSM method is as follows:The transformed equation of surface roughness prediction is as follows:Equation 10 is derived from Eq. 9 by substituting the coded values of x1, x2, x3 and x4 in termsof ln s, ln f , lnαand ln r. The analysis of the variance (ANOV A) and the F-ratio test have been performed to justify the accuracy of the fit for the mathematical model. Since the calculated values of the F-ratio are less than the standard values of the F-ratio for surface roughness as shown in Table 4, the model is adequate at 99% confidence level to represent the relationship between the machining response and the considered machining parameters of the end milling process.The multiple regression coefficient of the first order model was found to be 0.5839. This shows that the first order model can explain the variation in surface roughness to the extent of 58.39%. As the first order model has low predictability, the second order model has been developed to see whether it can represent better or not.The second order surface roughness model thus developed is as given below:where Y2 is the estimated response of the surface roughness on a logarithmic scale, x1, x2, x3 and x4 are the logarithmic transformation of speed, feed, radial rake angle and nose radius. The data of analysis of variance for the second order surface roughness model is shown in Table 5.Since F cal is greater than F0.01, there is a definite relationship between the response variable and independent variable at 99% confidence level. The multiple regression coefficient of the second order model was found to be 0.9596. On the basis of the multiple regression coefficient (R2), it can be concluded that the second order model was adequate to represent this process. Hence the second order model was considered as an objective function for optimization using genetic algorithms. This second order model was also validated using the chi square test. The calculated chi square value of the model was 0.1493 and them tabulated value at χ2 0.005 is 52.34, as shown in Table 6, which indicates that 99.5% of the variability in surface roughness was explained by this model.Using the second order model, the surface roughness of the components produced by end milling can be estimated with reasonable accuracy. This model would be optimized using genetic algorithms (GA).5.2 The optimization of end millingOptimization of machining parameters not only increases the utility for machining economics, but also the product quality toa great extent. In this context an effort has been made to estimate the optimum tool geometry and machining conditions to produce the best possible surface quality within the constraints.The constrained optimization problem is stated as follows: Minimize Ra using the model given here:where xil and xiu are the upper and lower bounds of process variables xi and x1, x2, x3, x4 are logarithmic transformation of cutting speed, feed, radial rake angle and nose radius.The GA code was developed using MATLAB. This approach makes a binary coding system to represent the variables cutting speed (S), feed rate ( f ), radial rake angle (α) and nose radius (r), i.e. each of these variables is represented by a ten bit binary equivalent, limiting the total string length to 40. It is known as a chromosome. The variables are represented as genes (substrings) in the chromosome. The randomly generated 20 such chromosomes (population size is 20), fulfilling the constraints on the variables, are taken in each generation. The first generation is called the initial population. Once the coding of the variables has been done, then the actual decoded values for the variables are estimated using the following formula: where xi is the actual decoded value of the cutting speed, feed rate, radial rake angle and nose radius, x(L) i is the lower limit and x(U) i is the upper limit and li is the substring length, which is equal to ten in this case.Using the present generation of 20 chromosomes, fitness values are calculated by the following transformation:where f(x) is the fitness function and Ra is the objective function.Out of these 20 fitness values, four are chosen using the roulette-wheel selection scheme. The chromosomes corresponding to these four fitness values are taken as parents. Then the crossover and mutation reproduction methods are applied to generate 20 new chromosomes for the next generation. This processof generating the new population from the old population is called one generation. Many such generations are run till the maximum number of generations is met or the average of four selected fitness values in each generation becomes steady. This ensures that the optimization of all the variables (cutting speed, feed rate, radial rake angle and nose radius) is carried out simultaneously. The final statistics are displayed at the end of all iterations. In order to optimize the present problem using GA, the following parameters have been selected to obtain the best possible solution with the least computational effort: Table 7 shows some of the minimum values of the surface roughness predicted by the GA program with respect to input machining ranges, and Table 8 shows the optimum machining conditions for the corresponding minimum values of the surface roughness shown in Table 7. The MRR given in Table 8 was calculated bywhere f is the table feed (mm/min), aa is the axial depth of cut (20 mm) and ar is the radial depth of cut (1 mm).It can be concluded from the optimization results of the GA program that it is possible toselect a combination of cutting speed, feed rate, radial rake angle and nose radius for achieving the best possible surface finish giving a reasonably good material removal rate. This GA program provides optimum machining conditions for the corresponding given minimum values of the surface roughness. The application of the genetic algorithmic approach to obtain optimal machining conditions will be quite useful at the computer aided process planning (CAPP) stage in the production of high quality goods with tight tolerances by a variety of machining operations, and in the adaptive control of automated machine tools. With the known boundaries of surface roughness and machining conditions, machining could be performed with a relatively high rate of success with the selected machining conditions.6 ConclusionsThe investigations of this study indicate that the parameters cutting speed, feed, radial rake angle and nose radius are the primary actors influencing the surface roughness of medium carbon steel uring end milling. The approach presented in this paper provides n impetus to develop analytical models, based on experimental results for obtaining a surface roughness model using the response surface methodology. By incorporating the cutter geometry in the model, the validity of the model has been enhanced. The optimization of this model using genetic algorithms has resulted in a fairly useful method of obtaining machining parameters in order to obtain the best possible surface quality.中文翻译选择最佳工具，几何形状和切削条件利用表面粗糙度预测模型端铣摘要：刀具几何形状对工件表面质量产生的影响是人所共知的，因此，任何成型面端铣设计应包括刀具的几何形状。
夹具设计中英文对照
Optimization of fixture design with consideration of thermal deformation inface milling考虑端铣中热变形的最佳化夹具设计Huang, YingAbstract摘要Effective methods of fixture design are proposed to reduce machining error caused by cutting heat in face milling. Experiments show that thermal effect is critical to final error in the finish cut and that it dominates cutting accuracy. Therefore, a mathematical model is structured of the cutting heat source on behalf of the cutting tool, and the flatness error generation process in face finishing is demonstrated by computational simulation based on the moving cutting heat source model with FEW Concerning surface flatness due to the moving cutting heat source for relatively thin plate-shaped workpieces, different methodologies have been proposed to reduce flatness error, namely, the application of additional supports and optimization of the fixturing support layout. Cutting experiments and computational analyses show the effectiveness of the additional supports and the optimization methodology applied on the fixture design in view of flatness error due to cutting heat. The proposed methodologies are applicable and beneficial to improve cutting accuracy not only of plate-shaped workpieces but also of other geometry workpieces.用于减小端铣中因切削热而引起的加工误差的有效的夹具设计方法已经被提出。
汽车车身焊装夹具设计概述
汽车车身焊装夹具设计概述【摘要】汽车车身焊装夹具设计是汽车生产中至关重要的环节，它直接影响着汽车的质量和生产效率。
夹具设计的重要性在于能够确保车身零部件在焊接过程中的精准位置，避免因位置不准确导致的焊接质量问题。
汽车车身焊装夹具通常可以分为定位夹具、夹紧夹具和支撑夹具等不同类型，每种类型都有其特定的应用场景。
在设计汽车车身焊装夹具时，需要遵循一定的原则，如提高夹具的刚性和稳定性、考虑可靠性和易用性等。
设计流程包括需求分析、方案设计、构造设计、工艺设计和试制等环节。
而汽车车身焊装夹具的应用涵盖了车身结构件焊接、焊接装配和流水线生产等多个方面。
展望未来，随着汽车技术的不断发展，汽车车身焊装夹具设计将继续朝着智能化、自动化的方向发展，以提高生产效率和产品质量。
汽车车身焊装夹具设计是汽车制造领域中不可或缺的环节，其发展前景可期。
【关键词】汽车车身、焊装夹具设计、重要性、分类、原则、流程、应用、发展前景、总结1. 引言1.1 汽车车身焊装夹具设计概述汽车车身焊装夹具设计是在汽车制造工艺中起着至关重要的作用的。
夹具设计的好坏直接影响到汽车的质量和生产效率，因此在汽车制造领域，车身焊装夹具设计被视为至关重要的一环。
汽车车身焊装夹具设计需要考虑到多种因素，包括车身结构、焊接点的位置、焊接工艺要求等。
通过合理设计夹具，可以使得焊接过程更加精确和高效，避免因为瑕疵而导致车身质量问题，提高生产效率。
在汽车制造中，汽车车身焊装夹具可以根据其功能和结构的不同来分类，主要包括定位夹具、固定夹具、支撑夹具、夹持夹具等。
每种夹具在焊装过程中都有着不可或缺的作用。
需要注意的是，在汽车车身焊装夹具设计过程中，应当遵循一定的设计原则，如合理布局、结构简洁、易于操作等。
设计流程也应该遵循一定的步骤，包括需求确认、方案设计、试验验证等。
汽车车身焊装夹具在实际生产中有着广泛的应用，不仅可以用于大型汽车的焊装，还可以用于小型汽车和特种车辆的制造。
机械加工专业毕业设计外文翻译
附录ToolPurposeUpon completion of this unit, students will be able to:* Rough and explain the difference between finishing.* Choose the appropriate tool for roughing or finishing of special materials and processing.* Recognition Tool Cutting part of the standard elements and perspective.* The right to protect the cutter blade.* List of three most widely used tool material.* Description of each of the most widely used knives made of the material and its processing of Applications.* Space and inclination to understand the definition.* Grinding different tools, plus the principle of space and inclination.* To identify different forms of space and the inclination to choose the application of each form.The main points of knowledge:Rough-finished alloy steel casting materialScattered surplus carbide ceramic materials (junction of the oxide) ToolWith a chip breaking the surface roughness of the D-cutter knives diamondsAfter Kok flank behind the standard point of (former) angle off-chipSide front-side appearance and the outline of the former Kok (I. Kok)Grinding carbon tool steel front-fast finishing horn of rigid steelDouble or multiple-side flank before the dip angle oblique angleSurface-radius Slice root for curlingRough and finishing toolCutting speed only in the surface roughness not required when it is not important. Rough the most important thing is to remove the excess material scattered. Only in surface roughness of the finishing time is important. Unlike rough, finishing the slow processing speed. Chip off with the D-knives, better than the standard point of knives, in Figure 9-10 A, is designed for cutting depth and design, for example, a 5 / 16-inch box cutter blade of the maximum depth of cut 5 / 16 inches, and an 8 mm square block will be cutting knives Corner to 8 mm deep, this tool will be very fast Corner block removal of surplus metal. Slice merits of the deal with that, in a small blade was close thinning. This tool is also a very good finishing tool. But please do not confuse the thin band Tool and Tool-off crumbs. A chip-off is actually counter-productive tool to cut off the chip flakes.And the standard tool of the Corner, compared with chip breaking tool for the Corner is in its on and get grooving, Figure 9-10 B. This tool generally used to block the Corner of rough finishing. While this tool Corner blocks have sufficient strength to carry out deep cut, but the longer the chip will cut off the plane around after shedding a lot of accumulation. Chip is so because the tangles and sharp, and theoperator is a dangerous, so this is a chip from the need to address the problem. Double, or triple the speed of the feed will help to resolve, but this will require greater horsepower and still easily chip very long. Because of the slow processing, however, this action will be a good tool but also because of the small root radius of the processing will be a smooth surface. Especially when processing grey cast iron especially.Cutting Tools appearanceAppearance, sometimes called the contour of the floor plan is where you see the vision or the top down or look at the surface. Figure 9-11 illustrate some of the most common form, those who could be on the cutting tools and grinding out successfully be used. National Standards in its thread-cutting tool on a tiny plane can be as GB thread, the Anglo-American unity and international standards screw threads. A special tool to outline the thread of the plane is to be ground into the correct size.Tools Corner fixedCorner to a number of knives around the 15 degree angle while the other knives and cutting of the straight. When the mill in Figure 9-12 A and 9-12 B, for example by the space and the inclination, these must factor into consideration in the review. Figure 9-12 B Tool Corner block the angle is zero, compared with 9-12 A map is a heavier cutting tools, and the 9-12 A map will take more heat. The same amount of space in front of the two cases are the same.Tool Corner block component and the angleFigure 9-13 Tool Corner block an integral part of the name, and plans 9-14 point of the name, is the machinery industry standards.Grinding Wheel Tool Corner BlockWhen the cutter is fixed in the middle of Dao, Tool Corner block can not be the grinding. Can not do so for the reasons: because of the large number of Dao and extra weight, making Corner together with the grinding is a clumsy and inefficient way. Too much pressure could be added to round on the sand. This can cause the wheel Benglie wheel or because of overheating and the rift on the Corner Tool damage. There are grinding to the possibility of Dao.GrindingA craftsman in his toolbox, should always be a small pocket lining grinding tool. Alumina lining a grinding tool as carbon tool steel and high speed steel tool tool. The silicon carbide lining grinding tool grinding carbide cutting tools. Cutting Tools should always maintain smooth and sharp edge, so that the life expectancy of long knives and processing the surface smooth.Cutting tool materialsCarbon tool steel cutter Corner block usually contains 1.3 percent to 0.9 percent of carbon. These make use of the cutting tool in their tempering temperature higher than about 400 degrees Fahrenheit (205 degrees Celsius) to 500 degrees Fahrenheit (260 degrees Celsius) remained hardness, depending on the content of carbon. These temperature higher than that of carbon tool steel cutter will be changed soft, and it will be the cutting edge. Damaged. Grinding blades or cutting speed faster when using carbon tool steel cutter will be made of the blue, this will be in the imagination. Toolwill be re-hardening and tempering again. So in a modern processing almost no carbon as a tool steel blade.Low-alloy steel cutting tool in the carbon steel tools added tungsten, cobalt, vanadium alloying elements such as the consequences. These elements and the hardness of high-carbon carbide. Increased tool wear resistance. Alloy tool steel that is to say there will be no hard and fast with hot red when the knife's edge can still continue to use it. Low-alloy steel cutting tool is relatively small for a modern processing.High-speed steel with tungsten of 14 percent to 22 percent, or Containing 1.5% to 6% of the W-Mo (molybdenum which accounted for 6 percent to 91 percent). From high-speed steel tool made of a rigid heat, some high-speed steel also contains cobalt, which is formed of rigid factor. Cobalt containing high-speed steel tool can maintain hardness, more than 1,000 degrees Fahrenheit (or 540 degrees Celsius) blade will become soft and easily damaged. After cooling, the tool will harden. When grinding, you must be careful because of overheating and cold at first, so that profile Benglie Zhucheng a variety of metal alloy materials have a special name called Carbide, such as containing tungsten carbide cobalt chrome. In little or iron carbide. However, its high-speed steel cutting speed than the maximum cutting speed is higher 25 percent to 80 percent. Carbide Tool General for cutting force and the intermittent cutting processing, such as processing Chilled Iron.The past, Carbide Tool is mainly used for processing iron, but now carburizing tool for processing all the metal.Carbide Tool into the body than to the high-speed steel tool or casting - lighter alloy cutting tools, because tend to be used as a tool carbide cutting tools. Pure tungsten, carbon carburizing agent or as a dipping formation of the tungsten carbide, suitable for the cast iron, aluminum, non-iron alloy, plastic material and fiber of the machining. Add tantalum, titanium, molybdenum led to the carbon steel The hardness of higher tool, this tool suitable for processing all types of steel. In manufacturing, or tungsten steel alloy containing two or more of a bonding agent and the mixture is hard carbon steel tool, is now generally containing cobalt, cobalt was inquiry into powder and thoroughly mixed, under pressure Formation of Carbide.These cutting tools in the temperature is higher than 1,660 degrees F (870 degrees C) can also be efficiently used. Carbide Tool hardware than high-speed steel tool, used as a tool for better wear resistance. Carbide Tool in a high-speed Gangdao nearly three times the maximum cutting speed of the cutting rate cutting.Made from diamonds to the cutting tool on the surface finish and dimensional accuracy of the high demand and carbide cutting tools can be competitive, but these tools processing the material was more difficult, and difficult to control. Metal, hard rubber and plastic substances can be effective tool together with diamonds and annoyance to the final processing.Ceramic tool (or mixed oxide) is mixed oxide. With 0-30 grade alumina mixture to do, for example, contains about 89 percent to 90 percent of alumina and 10 percent to 11 percent of titanium dioxide. Other ceramic tool is used with the tiny amount of the second oxides Mixed together the cause of pure alumina.Ceramic tools in more than 2,000 degrees F (1095 degrees C) temperature of the work is to maintain strength and hardness. Cutting rates than high-carbon steel knives to 50 percent or even hundreds of percentage. In addition to diamonds and titanium carbide, ceramic tool in the industry is now all the materials of the most hard cutting tool, especially at high temperatures.Tao structure easily broken in a specific situation, broken only carbon intensity of the half to two-thirds. Therefore, in cut, according to the proportion of cutting and milling would normally not be recommended. Ceramics cutting machine breakdown of failure is not usually wear failure, as compared with other materials, their lack of ductility and lower tensile strength.In short, the most widely used by the cutting tool material is cut high-speed steel, low alloy materials and carbide.Gap and dipSpace and inclination of the principle is the most easily to the truck bed lathe tool bladed knives to illustrate. Shape, size of the gap, and dip the type and size will change because of machining. Similarly a grinding tool Corner block is just like brushing your teeth.Gap tool to stop the edge of friction with the workpiece. If there is no gap in Figure 9-15A in the small blades, knives and the side will wear will not be cutting. If there are gaps in Figure 9-15 B, will be a cutting tool. This basic fact apply to any type of tool.Clearance was cutting the size depends on material and the cutting of the material deformation. For example, aluminum is soft and easy to slightly deformed or uplift, when the cutter Corner into space within the perspective and the perspective of the space under, the equivalent in steel mill and will very quickly broken. Table 9-1 (No. 340) that different materials grinding space and perspective.The correct amount of space will be properly protected edge. Too much space will cause the blade vibration (fibrillation), and may edge of total collapse. Tool Corner for the slab block must have a backlash, behind (in front) gap, knife and cut-corner. The main cutting edge is almost as all the cutting work at the cutting edge of the cutting tool on the edge, on the left or right-lateral knives, or cutting tool in the end, cut off on a cutter.Backlash angle for example, the role of a lathe tool Corner to the left block when it mobile. If there is no backlash Kok, Fig 9-16 A, with the only tool will be part of friction rather than cutting. If a suitable backlash Kok, Fig 9-16 B, will be cutting edge and will be well supported. If I have too many gaps, Fig 9-16 C, the edge will not support leading tool vibration (fibrillation) and may be completely broken.Tool gap to the front or rear of the role when it fixed to zero, as shown in Figure 9-17. If not in front of the Gap. Figure 9-17 A, the tool will not only friction and cutting. If a suitable space in front, Fig 9-17 B, but also a good tool will be cutting edge will be well supported. If a big gap in front of Ms, Fig 9-17 C, the tool will lack support, will have a vibrate, and cutting edge may be pressure ulcer.Figure 9-18 illustrate the gap in front of a lathe tool, when it with a 15 degree angle when fixed. The same amount of space on the front fixed to zero, and around thecutter, but the tool is the relatively thin. So the heat away from the blade less. Typically, front-side or front-not too big in Figure 9-19. It is usually from zero degrees to 20 degrees change, an average of about 15 degrees. There are clear advantages, according to the following: good cutting angle so that the cutting edge of the work was well, but relatively thin chips. Cutting Tools is the weakest part. By the former angle, the blade In the form of points around the workpiece. Cutting Edge shock will cause the entire tool vibration. When cutting the work nearly completed, the final section of metal was to ring, packing iron sheet or tangles in the form of the metal ball away gradually replaced by direct removal. Pressure tends to stay away from the workpiece cutting tool rather than narrow the gap between its parts. 9-19 A in the plan was an example of the use of a 30-degree lateral Cutting Angle tool processing thin slice example. A mathematical proof of the plan 9-19 B in the right-angle triangle trip is to expand the use of a map 9-19 A right triangle in the same way, that is, in the direction of upward mobility to feed a 0.010 inch. Right triangle adjacent to the edge (b) and feed 0.010 feet equivalent.The following formula using triangulation to explain:Kok cosine A = right-angle-B / C XiebianOr cosine of 30 degrees = b / c0.886 = b/0.010b = 0.866 * 0.010b = 0.00866 (bladed too thin)When the mobile tool, the purpose of front-to be processed to eliminate from the surface of the cut-cutting tools. This angle is usually from 8 degrees to 15 degrees, but in exceptional circumstances it as much as 20 degrees to 30 degrees. If there is no gap in Figure 9-20 A, cutting tools will be tied up, sharp beep, and the rivets may be the first to die away. The appropriate space, in Figure 9-20 B, cutting tool will be cutting well.A manufacturing plant or cut off the fast-cutter blade with three space, in a root-surface or surface and the other in bilateral level, in Figure 9-21. If a tool Corner block from the date of the face, It can have up to five space, in Figure 9-22. Grooving tool sometimes known as area reduction tool used to cut a groove in the shallow end of the thread.Inclination is the top tool inclination or, in the Tool Corner block on the surface. Changes depending on the angle of the cutting material. Improvement of the cutting angle, the blade shape, and guidelines from the chip from the edge of the direction. Chip dip under the direction named. For example, if a chip from the edge cutter outflow, it is called anterior horn. If the chip to the back of the outflow, that is, to the Dao, which is known as the horn. Some mechanical error and the staff horn as a front-or knife corner.Single tool like Tool Corner block may be the only edge of the blade side oblique angle, or in the back, only to end on the edge of the horn, or they may have roots in the face or front surface of the main Cutting edge of the blade and cutting edge of the horn and a roll angle of the portfolio. In the latter case, cut off most of the surface with a cutter and a chip to the point of view in the tool horn and roll angle in bothdirections has been moved out.Two different roll angle in Figure 9-23 A and 9-23 B was an example. Angle depends on the size and type of material was processed.9-24 A map in Figure 9-24 B and gives examples of zero to a fixed cutter after the two different angle. In Figure 9-25 B and 9-25 A Tool to the regular 15-degree angle. Figure 9-26 tool to display a 15 degree angle fixed, but in this case a tool to roll angle after angle and the combination of form close to the workpiece. Double or multiple chips to lead the inclination angle of a mobile or two away from the edge of the back and side to stay away from the cutter.Comparison of various horn, shown in Figure 9-27, Corner of the horn of a negative point of view, and zero is the point of view. These dip in the Corner cutter on the manifestation of a decision in the hands of the processing needs of the pieces. After Kok was the size of the type of materials processing, and knives in Dao fixed on the way.The type of lateral oblique angleFigure 9-28 examples of tools Corner blocks and four different types of lateral oblique angle of the cross-sectional. Figure 9-28 A, is zero lateral oblique angle, like some of the brass materials, some bronze and some brittle plastic material is particularly necessary. Standard side oblique angle, in Figure 9-28 B, is the most common one of the bevel side. In the ductile material on the deep cut, easy to chip in the tool around the accumulation of many, and this will cause danger to the operator. The chip will become a deal with the problem. Such a tool to cut off the grey cast iron is the most appropriate.Chip laps volumes, Figure 9-28 C, is one of the best types of inclination, especially in the ductile material on the special deep cutting. Chip small crimp in close formation against the Dao of bladed knives against the will of the rupture. The chip rolled up to maintain a narrow trough of the chip will guarantee that the width of closely Lane V ol. The chip is very easy to handle. V olume circle with a chip is not a cut-chip.Chip cut off, in Figure 9-28 D, leading to chip in the corner was cut off, and then to small chips fell after the chip. The need to cut off a chip provides up to 25 percent of the force. This inclination of the stickiness of the steel is good.Gap KokWhen cutting any material time, the gap should always be the smallest size, but the gap should never angle than the required minimum angle small space. The gap is too small knives Kok will lead to friction with the workpiece. Choice of space at the corner to observe the following points:1. When processing hardness, stickiness of the material, the use of high-speed steel tool cutting angle should be in the space of 6 to 8 degrees, and the use of carbon tool steel cutter at the corner of the gap in size should be 5 degrees to 7 degrees.2. When the processing of carbon steel, low carbon steel, cast iron when the gap angle should be the size of high-speed steel tool 8 degrees to 12 degrees, and carbon tool steel cutter 5 degrees to 10 degrees.3. Scalability when processing materials such as copper, brass, bronze, aluminum,iron, etc. Zhanxing materials, space Kok should be the size of high-speed steel tool 12 degrees to 16 degrees, carbon steel knives 8 degrees to 14 , Mainly because of the plastic deformation of these metals. This means that, when the cutter and around them, the soft metal to some minor deformation or protruding, and this tool will be friction. At this time, we must have a tool on the additional space.刀具目的在完成这一个单元之后，学生将会能够:* 解释粗加工和精加工之间的差别。
汽车车身焊装夹具设计
汽车车身焊装夹具设计摘要：汽车车身通过冲压、焊装、涂装、总装配制造而成。
车身在焊装过程中要使用多点定位夹紧的专用夹具来保证各零件在焊接处的正确位置。
因为汽车工业的快速发展，大大提高了制造车身水平。
制造车身质量决定了整个车身的品质，而车身装焊设计中焊装线设计是重要组成部分，在设计的时候要充分的了解到产品的功能，认识产品的精确参数，方便在现实应用中增加安全性与实用性。
焊装夹具设计是不是合理，最后唯有通过生产实践检验，才可以证明是合格与优秀的，而在设计以前，一定要做到精益求精，使损失减少，创造出与时代需求相符的产品。
关键词汽车车身;焊装夹具;设计方法制作汽车的精度和汽车车体的生产周期与汽车焊接夹具的要求有关性特别高，在设计的时候我们要非常注意。
所以，确保汽车生产与制造质量的一个重要性程序就是设计与制造汽车焊接夹具，同时，也是需要很多的经验和制造、设计技术的一项工作，增强汽车焊接夹具的研究具备关键意义。
1车身焊装夹具简介焊装夹具基本由底板、支基、气控三部分组成。
焊装夹具用三坐标进行检测。
焊装夹具的常见结构有定位元件和夹紧元件。
定位元件有定位销、定位块。
定位块和定位销座均采用可调式结构，通过调整垫片数量的增减来调整定位块的精确位置。
定位块的定位面、销孔要求热处理后精加工。
夹紧机构有手动、气动两种夹紧方式。
杠杆式定位夹紧单元的基本类型有气缸固定式、双面夹紧机构、手动夹紧气路退回式等模式。
该类型适用于一般夹紧，该模块除了定位块、导向杆之外，其余的零件都是由压板的草图控制。
2焊装夹具的设计要点和常见问题焊装夹具的设计主要考虑焊接质量和人机工程。
为保证焊接质量,应合理确定薄板冲压件焊接搭接顺序,要合理确定定位点和定位方式，焊装夹具在运动过程中无干涉，设计夹紧气路时，考虑焊接完成后是否能取出整体零件。
人机工程能保证操作人员能够舒适、安全地工作，设计时考虑夹具平均操作高度、焊钳类型，基准平台可根据情况安置回转机构。
3车身焊接夹具设计的必要性在设计和制造车身的很多开发程序过程中，特别关键的一个程序就是车身焊接夹具设计，其直接关系着制造出产品的合格率。
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附录(英文文献及中英文对照)The designing features of automobile bodywelding fixtureAuto 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 thestamping 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 theprocedures 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 roleof critical dimensions. In addition, assembly and welding fixture structure should be easy to operate, saving, security and easy handling characteristics of the workpiece.汽车车身焊装夹具的设计要点汽车车身夹具是用来把所需车身冲压件按要求定形、定位并夹紧，组合成车身组件、合件、分总成及总成，同时利用合适的焊接方法使其形成各自焊合件整体。