Applied Mechanics and Materials Vols. 215-216

Abstract: A quasi-static analytical model for needle bearing was established base on the rolling contact theory and the force analysis of needle bearing,and the model was caculated by computer program.Conclusions are drawn as follows by analysis of needle bearing load distribution in different misalignment,different load,different clearance,different speed,different crown drop of needle:work of bearing would be influenced if misalignment so big,the influence of misalignment must be considered when the engineer determine the clearance of beearing, it’s rotational speed has small influence on the load distribution of bearing ,reasonable choise of crowning of needle could be enhanced the lifetime of needle bearings.

Abstract: A novel radial telescopic tire building drum is proposed to meet the radial tire production requirements. After the discussion of the mechanical structure and transmission principle of this mechanism, the kinematics equations together with the formulas of contraction ratio and pressure angle are established. In order to optimize the characteristics of force-transfer, when taking the interference condition into consideration, a kinematics design method of this novel radial telescopic building drum is proposed, which can obtain the minimal value of mechanism maximum pressure angle and satisfy the demand of contraction ratio. The most important feature of this building drum is that the external shell is driven by the internal shell. Designer can derivative more design schemes by applying this transmission principle.

Abstract: The new approach for approximately synthetically spatial C-S Binary with adapt saddle-fitting is presented, given the definition of adapt saddle-fitting cylinder surface and approximate cylinder surface point, constructed unified mathematical model of adapt saddle-fitting cylinder surface fitting of spatial curve and unified error standard . It is solved by saddle-point programming. The example shows optimization methods are effective and global convergent.

Abstract: This paper introduced the design requirements, structure, as well as the working principle of vermicelli strapping machine. The process of strapping mainly divided into two steps. The first step is to make the cotton thread wrapped around the vermicelli, during which, the speed of wrapping is greatly improved because the distance of the winding is shorten by the innovative teardrop-shaped winding track. The second step is to knot the cotton thread that wrapped the vermicelli. The type of knot used in this strapping machine can be implemented on machine; besides, the knot is so tight that it’s not easy to be loosed. By adjusting the position of knotting structure, the gap of bundled vermicelli is reduced. As a result, the vermicelli will be strapped tight.

Abstract: Optical fibre connnector is the most typical optical passive device in optical fibre communication industry with its various categories and structures. Optical fibre adapter is indispensable component when optical fibre connectors connect to each other. The base is the key element of optical fibre adapter. But its feeding in the factory is completely done by hand. This way is of great labour intensity and low production efficiency, so it can not meet the production need. This paper aims to design a compound automatic feeding device for the optical fibre adapter base. The device includes five modules: vibration screening mechanism, jacking-up mechanism, opening-closing mechanism, combiner mechanism, linear vibratory conveying mechanism, is to complete the automatic feeding. The control system is based on MCS51 singlechip computer technology. Through the research, it can be a good solution to the automatic feeding of the opical fibre adapter base.

Abstract: This paper aims to design a knee rehabilitation device which can help the knee patients to perform movement in bending leg manner. And in that way the rehabilitation process will be improved greatly. The design of the device includes the mechanical main body design, driving motor, and control circuit which contains the keyboard setting, display unit and clock unit. Through the pulse width modulation (PWM) technology the stepping motor is driven and the automatic bent in leg is achieved. During the exercise the following information is known: the starting time, the lasting time, the angle of movement and the speed of movement. The micro controller unit (MCU) is responsible for the information processing from both the key and liquid crystal display (LCD). After the key inputs the given parameters the stepping motor can output the desired motions. Meanwhile, the LCD can display the input information. Now the project has accomplished the preliminary design, and the concrete scheme is shown in this paper.

Abstract: 3D models of propellant filling equipment were constructed by using Autodesk Inventor, and assembly relation model was established by using connection graph method. Movement attribute was set and the models were romanced in Multigen Creator. A virtual scene of propellant filling equipment was set up, and assembly process demonstration and interactive operation simulation were achieved by using Vega Prime. Maintenance personnel training in the virtual assembly environment gets a good result.

Abstract: In this paper，we designed a new kind of aluminum silicate fiber paperboard machine basing on the characteristic of aluminum silicate fiber and papermaking technology while some related process was studied in this paper. The aluminosilicate fiber board was prepared by the process of wet forming vacuum filter and microwave drying. The well strength performance was obtained by adding the high temperature resistant inorganic and organic adhesives. Considering these properties, we designed the aluminum silicate fiber paperboard machine with the pulp consistency of 1～2%, the paper machine speed of 1.5m/min, the width of 2m, the apparent density of 200～350Kg/m3 and the thickness of 20mm～50mm. The insulation board can be resistant up to 1200°C.

Abstract: As the main bearing part in a turbine blade, the root carries most of the loads of the whole blade. The improvement of the root structure can be used to enhance the operation reliability of steam turbine. The research on design optimization for double-T root and rim of a turbine blade was conducted by three-dimensional finite element method. Based on the APDL (ANSYS parametric design language), a multi-variable parametric model of the double-T root and rim was established. Twelve characteristic geometrical variables of the root-rim were optimized to minimize the maximum equivalent stress. The optimal structure of the double-T root-rim is obtained through the optimization. Compared with the original structure, the equivalent stress level of the root and rim has a significant reduction. Specifically, the maximum equivalent stress of root and rim reduces by 14.25% and 13.59%, respectively.

Abstract: Final assembly deviations of mechanical products are determined by accumulation, coupling and propagation of all parts tolerances in the assembly system, whether the final assembly meets the design specification or not can only be obtained after the assembly is completed. The verifiable design model in this paper took object-oriented Petri net as logic lever carrier, and embedded deviation in form of matrix to Petri net, and then analyzed and calculated the assembly deviation from the logical and numerical lever synchronically, after that the final cumulative deviation is obtained. If the cumulative deviation exceeded precision limit, key influence factors to the cumulative deviation could be analyzed. The assembly design defect is identified and located in the design process, and the synchronization of design and verification is achieved. This model has some excellent characteristics, such as modularization, reusability, and capability to describe structural logical relationships.