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haps more functional, economical,and durable products. To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a bination of properties.8. Select carefully, stock and integral ponents.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly. Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading. 3. Reviews the fundamentals of stress and defection analysis. 4. Introduces fatiguefailure theory with the emphasis on stresslife approaches to highcycle fatigue design, which is monly used in the design of rotation machinery. 5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue. 6. Investigates shaft design using the fatigueanalysis techniques. 7. Discusses fluidfilm and rollingelement bearing theory and application 8. Gives a thorough introduction to the kinematics, design and stress analysis of spur gears , and a simple introduction to helical ,bevel ,and worm gearing. 9. Discusses spring design including pression ,extension and torsion springs. 10. Deals with screws and fasteners including power screw and preload fasteners. 11. Introduces the design and specification of disk and drum clutches and brakes.Machine DesignThe plete design of a machine is a plex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today39。s designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective ponents. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked. The puter is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on puter capabilities, have made possible the concepts of puter aided design (CAD) and puteraided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel39。39。s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on. If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the pletely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brandnew design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not