Advanced Materials Research Vols. 694-697

Abstract: The three basic criterions of pumping unit were analyzed. The criterions could be extracted from power curve of pumping unit in one stroke. When the pumping unit was adjusted by one criterion, it could also fit the other criterions. Under this condition the pumping unit could be considered as well balance. The practical testing and data prove that the pumping unit can meet the requirements of criterion one and two, approach criterion three after adjusting by power method.

Abstract: A knowledge-based cutter head design theory of shield tunneling is proposed because of lacking integrated cutter head design theory in China. A three-dimensional theory system is structured by the Hall three-dimensional theory. The basic concepts of the mentioned theory and connotations of knowledge model which takes cutter head of EPB shield tunneling as an example are also expounded in detail. The application in practice shows that the knowledge-based cutter head design theory is feasible. It is important to improve design quality, efficiency and reduce cost in cutter head design.

Abstract: The spreading soil device of rice factory seedling has been designed. In study the V shape bulldozing plate drum dump structure has been designed that focused on the high quality requirements of the super rice seedlings, the diameter and length of the V shape bulldozing plate drum dump and the thickness M of the V shape bulldozing plate has been designed, a force model of the soil in the dumping course and analyze the effect of spiral and operate width of the V shape bulldozing plate to dump performance also has been established. Finally, the assembled reasonableness between the drum dump and other components has been established through the 3D solid modeling of Pro / E software. The thickness and uniformity of spreading soil has been guaranteed also the quality of seedling emergence has been ensured by designing the device.

Abstract: The movements to personalized products and up-to-date technology speed up the time of products become obsolete (partially obsolete) before the end of their life. Thus, the capability to design product more flexible is the key competitive factor leads to secure product cost and extend the product life time. In this paper, the (re)design methodology that leans on Axiomatic design and TRIZ has been developed and implemented to enhance flexibility of a product meeting customer’s requirements and support future change. The paper shows, through a case study, how the flexible are created for specific industrial product: electric towing vehicle.

Abstract: This article introduces the structure, working principle, simple calculation and main application of the linear motion unit.

Abstract: This paper studies the auxiliary slot design technique for cogging torque minimization basing on an 8-pole/12-slot SPM servo motor. When the stator tooth coronas are unsaturated, the notching guidance given by analytical method can be testified effective in cutting down the cogging torque by FEM. But when the stator tooth coronas are saturated, the notching guidance is not effective any more. This phenomenon indicates that the saturation of stator tooth coronas has a significant impact on cogging torque. Thus, in auxiliary slot design, saturation effect should be considered; otherwise, counterproductive effects would occur.

Abstract: A methodology for mechanical products assembly design defect identification was presented based on assembly constraint verification tree (ACVT). An identification system framework, which consists of verification tree constructors, modifier, monitor and identification analyzer, was proposed. Modified design parameters were stored into modifier, monitor was employed to supervise design parameters variation in modifier and renew design parameters information in verification tree, identification analyzer decided the start or stop of verification according to stack information in monitor. A prototype system based on above identification system framework was developed, assembly design defects identification results for driving leg of parallel manipulators demonstrate that not only can it enhance identification efficiency for assembly design defects effectively, but also can implement dynamic relating identification for assembly design defects of mechanical products.

Abstract: Rigid cross-beam method is one of the most widely used calculation strategy for bridge transverse load distribution coefficient, which is based on grillage theory. However, the shear deformation of the main girder and the difference of transverse load distribution in longitudinal direction are ignored in the calculation process. In this paper, a generalized rigid cross-beam method are proposed based on the displacement beam theory and torsion theory of thin-walled bars, which can take account of the influence of shearing deformation, the difference of the transverse load distribution in longitudinal direction, and torsional behavior of the beam. Numerical simulation demonstrated that the proposed method possesses favorable accuracy and applicability.

Abstract: Although the function of Auto CAD is powerful, its professional pertinence is weak, and partuicularly it cannot satisfy the requirement for the efficient drawing and annotation of the common mechanical structure. The author of this paper has a discussion on the development principle and methods of a 2D General Mechanical CAD System (MACD). Faced up with all the requirements of the mechanical designing 2D drawing, and on the basis of the overall extracting the special features of the mechanical structure 2D primitives, the designing habits and the designing standards and specifications, all the function points of the system have been set up through the intersection and integration of the Auto CAD working mode and the functions of the system. A mechanical CAD system with a general drawing fucntion has been complished with a comprehensive use of the tools of the Auto CAD like function expansion, menu customization and programme development. Applied practice shows that this system has satisfied all the requirements for the mechanical desginers to make the drawings, annotations, enquiry for the standard data, the structure enquiry and quotations so that the designing efficiency has been greatly increased.

Abstract: The structure and size of the existing highway guardrail are mainly designed for mid-size and small-size vehicles, but lack of consideration for large-size vehicles with high gravity and large weight. Some typical highway accident were surveyed through which the guardrail in the central reservation was redesigned for preventing the large-size vehicles from crossing the guardrail according to the relevant norms issued by China. A scheme of double-layer high guardrail is proposed for preventing high gravity vehicles from the accident of rollover. The structure and size of guardrail is determined through the survey of vehicles type and traffic accident, and design renderings of the guardrail are obtained.