Applied Mechanics and Materials Vols. 184-185

Abstract: Analysis of the content in the stage of equipment engineering development equipment design and maintenance of design, putting forward the method of the quantitative evaluation of equipment maintainability. The instance studies have shown that this method is feasible.

Abstract: In order to realize the technical performance of high speed, high precision, high stability and high reliability for conjugated indexing mechanism with periodic intermittent rotary motion, a two cams structure has been designed, and its geometry size and profile curve was carefully determined. Also the calculation formula of the contour curve for CAM was deduced. Research achievement has been applied to new equipment of enterprise development, the working performance is stable and reliable, the production efficiency raised by 30% compared to the domestic industry. The mechanism has characteristics of simplified structure, improved transmission performance and low cost.

Abstract: Aiming at the present application of fault simulation technology based on virtual prototype, virtual prototype technology and fault injection technology were studied and analyzed, and the fault injection technology was improved. Taking a mechanical system as research subject, the mechanism of fault caused by a spring's fatigue failure was analyzed. The system's dynamic response of different fault phases was analyzed based on the system's virtual prototype. Finally, the occasion of fault occurrence, spring's stiffness dropping to between 90% and 91% of primary value, is confirmed. The simulation result provides characteristic information for preventing and diagnosing fault.

Abstract: This paper introduces an architecture of embedded precision internal grinding open CNC system based on decoupling design, described the decoupling design method and principle. In this design, ARM was the main hardware device for CNC system and the embedded operating system μc/os-ii was used as the software development platform. Decoupling design based CNC system can be good at dealing with multitask and ensure the real time of system control.

Abstract: To adapt to agile workshop environment, the reliability of reconfiguration machine tool was analyzed, and the mathematical models of reconfiguration machine tools’ reliability guideline was established. By modular design of reconfiguration machine tool, the general idea of machine tool reconfiguration oriented to reliability was presented. The machine tool reconfiguration method based on modularization was researched mostly in such aspects as relativity analysis, module reconfiguration of lacking ability parameter, module reconfiguration of redundancy ability parameter. The method solved the rapidity reconfiguration ability of machine tool in system reconfiguration, utilized availability resource reasonably.

Abstract: According to sensibility and output accuracy is effected by mechanical coupling of positive and negative piezoelectricity films, analysis change of vibration beam nodes which result from coupling of positive and negative piezoelectricity films. In this paper, a new mosaic method of mechanical coupling is proposed which based on structure of the vibration beam gyroscope; the numerical calculations which result from carrying out for 60mm alloyed vibration beam illustrate the sensitivity of the Vibrating-beam Piezoelectricity Gyroscope improved 6.64%. Simulation results demonstrate sensitivity is increased 6.57% and in line with the theoretical calculations.

Abstract: Life test of feeding mechanism cost too much time and capital. To solve these problems, applying Reliability Enhancement Testing (RET) to the feeding mechanism was advanced. Established and checked a virtual prototype model based on ADAMS, and the chain’s contact load spectrum was obtained under both common and enhanced conditions. The stress results are gotten after its finite element analysis in ANSYS. According to the load spectrums and stress result, the life of the chain joint and enhancement coefficient are gained under calculation in ANSYS/FE_SAFE. It can provide a good reference to fatigue based RET.

Abstract: Abstract. Mechanical design contains three part: firstly, organization design; according to working requirement of machine, properly choose transmission form and executive body, so as to realize mechanical movement, and the result is showed by mechanical movement diagram. Secondly, structural design; according to machine’s load level, Meeting the request of mechanical strength and service life consider Structure technology and assembly processes, and determine the machine’s parts and assembly drawings. And thirdly, accuracy design; according to the function requirement of machine, select the appropriate dimensional accuracy, shape accuracy and surface roughness, in order meet the requirement, raise product quality, and reduce costs at the same time. There has already been plenty of paper dealing with organization design and structural design, but very few dealing with accuracy design.

Abstract: Confirming method of minimum fresh air in air conditioning system of textile workshop is studied. Two types of existing confirming methods and emerging problems are analysed. On this basis, concept of the indoor air refreshing degree is introduced, through combining practical situations including labor intensity, workshop temperature, ventilations type and labor density in textile workshop, the new method of confirming minimum fresh air is put out. Taking a spinning workshop as example, the minimum fresh air is calculated, which shows that the new method not only insure air quality but also reduce fresh air consumption.

Abstract: For the complication and imprecision of the calculation of efficiency about variable hydraulic pump, based on system identification theory and thought of identification with the modeling，the general polynomial expression is proposed to describe the efficiency of variable hydraulic pumps and the functional relationship between parametric and to set up the model using the least square method of parameters identification, and calculation model of the efficiency is established as an example for a type of axial piston variable hydraulic pump, the model is verified by the experimental data, and it’s fitting accuracy is over 87%.