外文资料与中文翻译外文资料：Talking about the optimum Design for reduction boxSummary: reducer is gearing widely used among the all kinds of mechanical equipment. Gearbox design merits will be directly affect the drive performance of the transmission equipment. This article analysis of two main gearbox design optimization methods by contrast analysis, then , reducer design need to considering factors was presented .which is constraints restraint conditions ,object functions and variables, and so on.Key words : reducer optimizationTraditional gearbox design normally through repeated discussion together, check to determine the design, although it can get that meet the given criteria design effects, but generally not be the best. In order to make the reducer for best performance, you must be optimized for speed reducer, reducer optimization can different optimization goals. Except for some very special occasions, often can be divided into the form from the structure on the pursuit of the smallest size (weight), from the use of performance pursuit of maximum load capacity, from the economic point of view to consider pursuing the minimum fee, three class goals. First class goals and objectives of the second class of the reducer of a contradiction, i.e. mass (weight) and carrying capacity. To a certain volume, reducer load capacity is limited; in carrying capacity must, reducer volume (weight) of reduce is limited. Thus, these two types of objectives embodied in essence is the same. Just before a class to load capacity as design criteria, the size (weight) as the optimization goal; the latter category instead, to a certain size (weight) as design criteria, the carrying capacity as optimization goals. The third goal, will involve a significant number of factors, in addition to the design of the rationality of the reducer, also depends on the companys labor organization, management, equipment, personnel and material prices and other factors. But for designers, the goal of ultimately comes down to a first class or second class target, that is, reduce or increase the volume reduction gears its carrying capacity.First, single-stage optimal design of cylindrical gear reducer or increase its carrying capacity of the volume.Single-stage final drive, which can consist of a pair of conical gear, a pair of cylindrical gears or composed by the worm, has a simple structure, the quality of small, low cost, easy to use. But its main transmission ratio i= 0 not too large, the general i =0 7, and further enhance i =0 will increase the diameter of the driven gear, thereby reducing the ground clearance, and so driven gear heat treatment difficult. Widely used single-stage main gear box cars and light and medium goods vehicle driven by the bridge. Single Gear reducer size is minimized by the optimal design, is a 16 6-dimensional inequality constraint optimization problem, its mathematical model can be denoted as:minf(x)x=x1x2x3x4x5x6TR6 S.t.gj(x)0(j=1，2，3，16) Optimized design; meet the strength requirements reducer greatly reduce the size of, reducing material and design costs and increased efficiency and quality. Optimization method is closely associated with traditional design, optimize the design is based on the traditional design, follows the traditional design of large amounts of data accumulate in, while taking into account the traditional design of the relevant factors involved. Optimal design although traditional design of some, but the design still has its limitations so that it can be used in optimum design reliability technology, introduced in fuzzy logic, forming reliability optimization or reliability and other modern design, engineering design and technology by "hard" to "soft" development.Second, concrete mixer truck Optimal Design of gear reducer1.the main argumentsConcrete mixer truck mixer drum (tank) volume 8 10m3, maximum 12 angle, speed 2 4r/min and 10 12r/min (discharge of reverse speed); reducer, 131: 1 gear ratio for maximum output torque 60 kN m, require transmission of high efficiency, sealing, noise, interchange. 2.2 The structural design includes the front cover components, passive wheel assembly, the first stage planetary gear assembly, the second stage planetary gear assembly, the central component and the body flange 6 most of the components. Body connection between the use of bolts and pins and positioning, between the body and the inner ring gear pins using flexible set of institutions are set out. In order to facilitate the user in using assembly and disassembly, the main axis reducer design and installation of a 15 angle, flange axis can X, Y and Z direction of swing 6 , and use special spherical bearings as bearing. Into planetary gear bearings, the spring ring mounted on the lateral and axial bearing clearance 0.2 mm, reducer maximum dimensions 467 mm 460 mm 530 mm, total weight (without oil) to 290 kg.2.Dr