机械制造工艺中的合理化机械设计解析

机械制造工艺具备系统化、复杂化的特点,在具体实施操作的时候对技术的要求较高,机械化设计是机械制造工艺的一个重要组成。为此,文章在阐述机械化设计在机械制造工艺中重要地位的基础上,分析机械制造中机械化设计的工艺和流程,并就如何实现合理化的机械设计进行策略分析,旨在能够确保机械设计制造出的产品满足实际生产需要。

谈实施性机械化施工组织设计

分析了编制实施性机械化组织设计的必要性,详细介绍了如何编制实施性机械化组织设计及编制时的注意事项,以期指导实践,确保施工单位获得最佳的技术效益和经济效益。

基于TRIZ理论的无碳小车创新设计

文章通过对无碳小车进行能量分析、运动特性分析以及整体结构分析,找出设计存在的问题,建立问题模型;结合TRIZ理论的矛盾矩阵,确定所要研究的技术参数;通过矛盾矩阵,找出适应于无碳小车具体设计的发明原理;对无碳小车进行创新设计,并设计出一款具有稳定可靠、运动性能更佳的无碳小车。

车床尾座摇轮钻孔计数器的设计

本文设计了一种车床尾座摇轮自动计数的装置,属于纯机械化设计,结构简单,操作容易,无能耗,免于摇轮时数圈的麻烦,使钻孔工作更加方便快捷。

PJS-1型两翼式葡萄剪枝机的设计

为解决人工修剪葡萄藤劳动强度大、费用高和作业效率低等问题,设计了一种PJS-1型两翼式葡萄剪枝机械。该机采用拖拉机前挂式液压驱动方式,主机通过机架连接部装安装于拖拉机前部配重部位,液压马达分别驱动左、右及顶部的切削刀旋转,一次可以完成双行葡萄藤侧部与顶部枝叶的修剪工作。该机的使用不仅能够节省大量的人力、成本,降低劳动强度,提高劳动生产率,而且能够实现葡萄剪枝的连续、高效和机械化作业。

Swarm intelligence for mixed-variable design optimization

Many engineering optimization problems frequently encounter continuous variables and discrete variables which adds considerably to the solution complexity. Very few of the existing methods can yield a globally optimal solution when the objective functions are non-convex and non-differentiable. This paper presents a hybrid swarm intelligence ap-proach (HSIA) for solving these nonlinear optimization problems which contain integer, discrete, zero-one and continuous variables. HSIA provides an improvement in global search reliability in a mixed-variable space and converges steadily to a good solution. An approach to handle various kinds of variables and constraints is discussed. Comparison testing of several examples of mixed-variable optimization problems in the literature showed that the proposed approach is superior to current methods for finding the best solution, in terms of both solution quality and algorithm robustness.

Principle and Method for Structural Design of Digital Woven Fabric

Digital woven textiles are one of the latest research areas of digital textiles. The key of research on design of digital woven fabrics lies in structural design. Nowadays, the application of digital design technology has fundamentally changed the concept of structural design of woven fabric, giving rise to design methods and effects that were deemed impossible before. A study has been carried out to analyze the nature of woven structures and the methods of structural design. This paper proposes an innovative principle and method of structural design under digital design concept, on which the design of digital gamut weaves and establishment of weave-database were presented to meet the requirement of balanced interlacement. It is envisaged that the results of this study will enhance future research in creation of digital woven fabrics, with particular emphasis on digital jacquard fabrics. Meanwhile, this study is also laid the foundation for the intelligent design of woven textile.

Design and research on pneumatic vane motor roofbolter

On the basis of analysis of the present roofbolter’s structures, the pneumatic vane motor roofbolter was proposed and researched. Structure principle of MFT 80Y type pneumatic vane motor roofbolter was expounded, a new project of the rotary shearing mechanism with integrating pneumatic vane motor with epicyclic reduction gear unit was carried out, the mathematical model for optimum design of the rotary shearing mechanism was set up, and the optimum design for the rotary shearing mechanism was made by MATLAB Optimization Toolbox. Finally, performance of MFT 80 type pneumatic vane motor roofbolter made with optimum method and the on site experiment were introduced.

Alloying behavior and characterization of(CoCrFeNiMn)_(90)M_(10)(M=Al,Hf)high-entropy materials fabricated by mechanical alloying

The alloying behavior and microstructures of the(CoCrFeNiMn)_(90)M_(10)(M=Al,Hf)high-entropy alloy(HEA)powders fabricated by mechanical alloying were studied.The CoCrFeNiMn)_(90)Al_(10) powders have duplex solid-solution structures.In contrast,nanocrystalline HfNi_(3) anchoring in amorphous structures is found in the(CoCrFeNiMn)_(90)Hf_(10) powders.The(CoCrFeNiMn)_(90)Al_(10) powders show better ferromagnetic behaviors,mainly explained by the facilitated motion of the magnetic domain induced by the coherent interface between duplex phases.Combined with our previous work,the rules of forming solid-solution and amorphous phase in as-milled HEA powders are preliminarily proposed.It is found that,compared with the as-cast HEA reported previously,the variation range of mixing enthalpy with atomic size difference of the solid-solution formed in as-milled HEA powders is broader.Moreover,the variation ranges between mixing enthalpy and entropy with atomic size difference of the amorphous phase in HEA powder become wider than those of high-entropy bulk metallic glass.

A holistic examination of the load rating design of longwall shields after more than half a century of mechanised longwall mining

It is a commonly asked question:how big should the longwall shields be? The answer is a key aspect of a longwall mining feasibility study when the consequences of inadequately rated shields are considered.This paper addresses this question based on the measured nature of the loading environment in which shields are required to operate,the various geological and geometrical controls of that environment and the various links between their load rating,a range of other relevant shield design factors and the loss event they are required to prevent a major roof collapse on the longwall face.The paper concludes that despite the tremendous advances that have been made in shield design and load rating over the past50 years,the same drivers that caused longwall miners of the past to seek improved roof control on the longwall face via the use of ever-higher rated shields,are still as relevant today.However at the current time,the limits of the largest available longwall shields have yet to be tested,therefore industry focus for the foreseeable future should possibly be in achieving the maximum level of roof control on the face via their optimum operational use rather than considering further shield rating increases and incurring the inevitable downsides in terms of capital cost and shield weight.

Hybridizing artificial bee colony with biogeography-based optimization for constrained mechanical design problems

A novel hybrid algorithm named ABC-BBO, which integrates artificial bee colony(ABC) algorithm with biogeography-based optimization(BBO) algorithm, is proposed to solve constrained mechanical design problems. ABC-BBO combined the exploration of ABC algorithm with the exploitation of BBO algorithm effectively, and hence it can generate the promising candidate individuals. The proposed hybrid algorithm speeds up the convergence and improves the algorithm's performance. Several benchmark test functions and mechanical design problems are applied to verifying the effects of these improvements and it is demonstrated that the performance of this proposed ABC-BBO is superior to or at least highly competitive with other population-based optimization approaches.

Optimization Design of Silicon Micro - capacitive Accelerometer with PWM Technique

The property of silicon micro-capacitive accelerometer is analyzed and discussed by establishing the model of the sensor,to lay a basis for optimization design of sensor system structure. Discussed issues include the static modeling and dynamic behavior of the two commonly used structures,i.e., double-cantilever supported and four-beam supported structures, and also the measurement range of these devices.

Research on virtual dynamic optimization design for NC machine tools

Virtual dynamic optimization design can avoid the repeated process from de-sign to trial-manufacture and test.The designer can analyze and optimize the productstructures in virtual visualization environment.The design cycle is shortened and the costis reduced.The paper analyzed the peculiarity of virtual optimization design,and put for-wards the thought and flow to implement virtual optimization design.The example to opti-mize the internal grinder was studied via establishing precise finite element model,modi-fying the layout of Stiffened Plates and designing parameters of the worktable,and usingthe technology of modal frequency revision and the technology of multiple tuned damper.The result of optimization design compared the new grinder with the original grinder showsthat the entire machine's first orders natural frequency is enhanced by 17%,and the re-sponse displacement of the grinding-head has dropped by 28% under the first order natu-ral frequency and by 41% under second order natural frequency.Finally,the dynamic per-formance of the internal grinder was optimized.

Optimal design of dynamic and control performance for planar manipulator

A design and optimization approach of dynamic and control performance for a two-DOF planar manipulator was proposed.After the kinematic and dynamic analysis,several advantages of the mechanism were illustrated,which made it possible to obtain good dynamic and control performances just through mechanism optimization.Based on the idea of design for control(DFC),a novel kind of multi-objective optimization model was proposed.There were three optimization objectives:the index of inertia,the index describing the dynamic coupling effects and the global condition number.Other indexes to characterize the designing requirements such as the velocity of end-effector,the workspace size,and the first mode natural frequency were regarded as the constraints.The cross-section area and length of the linkages were chosen as the design variables.NSGA-II algorithm was introduced to solve this complex multi-objective optimization problem.Additional criteria from engineering experience were incorporated into the selecting of final parameters among the obtained Pareto solution sets.Finally,experiments were performed to validate the linear dynamic structure and control performances of the optimized mechanisms.A new expression for measuring the dynamic coupling degree with clear physical meaning was proposed.The results show that the optimized mechanism has an approximate decoupled dynamics structure,and each active joint can be regarded as a linear SISO system.The control performances of the linear and nonlinear controllers were also compared.It can be concluded that the optimized mechanism can achieve good control performance only using a linear controller.

Human-centered design of Stubble-Mulch Rotocultivator for Boat Tractor

With the development of mechanization popularity in rural area, agricultural machinery product not only needs to meet the production goals, and also requires the simple operation and human-centered. Human-centered design is always, on the basis of the user＇ s requirement and usage, to think over the issues by regarding operator as the center, and to design the products by emphasizing the ease of use and understandability during design and manufacture. In this study, Stubble-Mulch Rotocultivator for Boat Tractor （SMRBT） is chosen as the design object. The coordination approach of the user, machine and environment is discussed by deeply investigating their relationship, which is an empirical study of the human-centered technology of agricultural machinery.

Series Design of Large-Scale NC Machine Tool

Product system design is a mature concept in western developed countries. It has been applied in war industry during the last century. However,up until now,functional combination is still the main method for product system de-sign in China. Therefore,in terms of a concept of product generation and product interaction we are in a weak position compared with the requirements of global markets. Today,the idea of serial product design has attracted much attention in the design field and the definition of product generation as well as its parameters has already become the standard in serial product designs. Although the design of a large-scale NC machine tool is complicated,it can be further optimized by the precise exercise of object design by placing the concept of platform establishment firmly into serial product de-sign. The essence of a serial product design has been demonstrated by the design process of a large-scale NC machine tool.

Synthesis of biodegradable Mg-Zn alloy by mechanical alloying: Statistical prediction of elastic modulus and mass loss using fractional factorial design

Biodegradable Mg-Zn alloy was synthesized using mechanical alloying where a statistical model was developed using fractional factorial design to predict elastic modulus and mass loss of the bulk alloy.The effects of mechanical alloying parameters(i.e.,milling time,milling speed,ball-to-powder mass ratio and Zn content)and their interactions were investigated involving 4 numerical factors with 2 replicates,thus 16 runs of two-level fractional factorial design.Results of analysis of variance(ANOVA),regression analysis and R2 test indicated good accuracy of the model.The statistical model determined that the elastic modulus of biodegradable Mg-Zn alloy was between 40.18 and 47.88 GPa,which was improved and resembled that of natural bone(30-57 GPa).Corrosion resistance(mass loss of pure Mg,33.74 mg)was enhanced with addition of 3%-10%Zn(between 9.32 and 15.38 mg).The most significant independent variable was Zn content,and only the interaction of milling time and ball-to-powder mass ratio was significant as P-value was less than 0.05.Interestingly,mechanical properties(represented by elastic modulus)and corrosion resistance(represented by mass loss)of biodegradable Mg-Zn alloy can be statistically predicted according to the developed models.

岩心钻机轻量化设计的现状分析及建议

以液压动力头岩心钻机为研究对象,从材料轻量化设计、结构轻量化设计、模块轻量化设计的角度对国内外液压动力头岩心钻机的现状进行了分析比较,并针对国内岩心钻机轻量化设计在轻质材料选用、轻量化结构构造、液压系统优化、控制系统数字化和智能化研究等方面存在的问题提出了相应的解决方案,对我国轻量化岩心钻机的研发工作具有参考意义。

Experimental Study on Friction Characteristics of Caragana korshinskii Kom

Caragana korshinskii Kom, which is a kind of excellent shrubs, has strong resistance to windstorms, and it is also a kind of forage that is of high nutritional value as well as a forming fuel conversion resource that is of high caloric. Caragana korshinskii Kom is of high lignifications after growing for a few years and the toughness of it is considerably high. Currently in China, equipments of harvesting and processing for ripe crops can hardly finish the mechanized production for Caragana korshinskii Kom. Friction characteristics of woody material for Caragana korshinskii Kom under different conditions should be given when the relevant operation machinery is designed, which can provide physical parameters for transportation of Caragana korshinskii Kom as well as the designing of relevant machinery. The paper bases on the research of friction characteristics between Caragana korshinskii Kom whose diameter of 7, 10, and 13 mm under sampling directions of 0°, 45°,and 90° and machinery materials that are commonly used such as steel plate, rubber sheet and so on, and meanwhile the test considers factors such as different conditions of Caragana korshinskii Kom, different materials of machines, different angles and so on. The data strongly suggests that the average static, dynamic friction coefficient between Caragana korshinskii Kom and steel plate is 0.399 711 and0.353 022, respectively; The average static and dynamic friction coefficient between Caragana korshinskii Kom and rubber sheet is 0.965 178 and 0.883 667, respectively. The maximum of static and dynamic friction coefficients is when the angle between the direction of sampling and the direction of movement is vertical. As the angle increased, the dynamic and static friction coefficient decreased. The friction coefficient between Caragana korshinskii Kom and steel plate were increased with the increase of the diameter of Caragana korshinskii Kom, but the diameter have no effect on the dynamic friction coefficient between Caragana korshinskii Kom and rubber plate. The conclusion of this paper can provide references for research on machines that are relevant to transportation and particle forming of Caragana korshinskii Kom.

一种圆竹弯曲加工设备

我国竹材资源丰富,利用空间广阔,然而,广泛应用于家具行业的圆竹弯曲构件的加工没有跟上整个家具行业机械化和智能化的步伐和未来趋势。在传统圆竹弯曲的两种方法中选择了更能呈现出圆竹一体化造型美感的加热弯曲法进行改进,针对圆竹烧热软化、弯曲相关的工艺尚不完善的现状,设计了一种简易圆竹弯曲设备。通过机械化动力机构传导为弯曲机构的方式对圆竹进行弯曲加工,以期在使其受力均匀的同时提高生产效率,为加快圆竹家具生产机械化和圆竹家具的产业化进程作出一点贡献,进一步使竹产业这一朝阳产业能够获得更好的发展。