Profile Precision of Hypoid Gears Controlled by Coordinate Measurements

The geometrical model of profile error is put forward to describe the tooth surface precision of hypoid gears. The influence of each machine tool setting error on profile error is investigated respectively, and the research of the associativity and compensativity among the machine tool errors are made. The setting errors of machine tool, the optimal modifying parameters and their value are got from the measurement coordinates of hypoid gear real tooth surface, and the adjusted manufacturing shows the geometrical precision of the tooth surface is improved effectively.     

Analysis and Discussion on Klinglnberg'' s Cyclo-Palloid Bevel Gear

Because of their machining characteristics,Klinglnberg' s sprial bevel gears have the advantage over Gleason' s in many ways,so that they are more and more widely used. This paper analyzes the meshing and machining properties of the gears and deduces the equations,normal curveture and contact ratio of tooth surface. It also lays a solid foundation for spreading and importing the Klinglnberg' s machine,and developing klinglnberg' s gears.     

Parameter Design for Machining Quenched Internal Helical Gears by EDM

Aiming at the problem of machining quenched internal helical gears, a method and its equipment are discussed and designed, which is used for machining quenched internal helical gears by EDM. Its characteristic and principle are proposed. The modifying design of the electrode gear and the calculating method of its modification coefficients is presented. Analyzing for the error of the machining equipment is done. The results show that this problem can be solved by EDM, the electrode gear is the modification gear of machined gear and the machining accuracy can be improved by controlling errors.     

Analysis of elastohydrodynamic lubrication of steel planar wormgear drive

Based on study of elastohydrodynamic lubrication (EHD) and meshing theory of planar worm gear drive, EHD model for the drive is proposed. Minimum film thickness on the whole contact area is calculated. EHD status for the drive is analyzed. The distributions of film thickness show that, EHD status during entry engagement is better than that during exit engagement, and EHD status of worm addendum area is better than that of dedendum area. Influencing factors such as work conditions and optimized parameters along with their effects were analyzed. Theoretical analysis suggests that the optimizing pressure angle and increasing worm pitch diameter have influence on improving lubricant performance of the planar worm gear drive.     

Transmission model of higher-order elliptical bevel gearing and motion simulation for interference checking

Higher-order elliptical bevel gear is a typical form of the noncircular bevel gear transmission.Space spherical coordinate system of the bevel gear meshing is set up based on the meshing theory of space transmission.The varying relationship among the pitch curve,tooth profile and mesh lines are analyzed,and the equation of the gear tooth surface is developed with matrix method based on space coordinate transformation.The basic parameters of the noncircular bevel gear such as transmission ratio,modulus and the number of teeth are designed,and detailed analysis of the influence of the eccentricity on the relevant parameters is carried out as well.By using discrete numerical method and three-dimensional software,the mathematical model of the tooth profile and virtual physical model of the noncircular bevel gear are established,and then simulation on its motion and interference checking are performed.Finally,the approach for design,calculation and generation of the tooth profile is obtained and its correction has been verified by experiment.     

Numerical Analysis of Thermo-Elastic Deformation for Cyindrical Gears

In this paper,both non-coupled numerical method of thermo-elastic deformation and coupled procedure for meshing gear are presented. The illustrative examples of gears applied in machine-tools and rolling mills show that this procedure is ralid and efficient.     

Key Techniques for Design and Manufacture of Micro Gas Turbine Engine

The characteristics of flow and combustion in micro gas turbine engine with the low Reynolds number and the high Mach number, the high Couette number and the low Biot number, as well as the ultra high duty ratio of combustion in very small space are analyzed, which are remarkably distinguished from those on macro scale. At the meantime, the limitation of traditional dynamic lubrication theory at ultra high speed on micro scale is presented, and the possibility of making the gas bearing to be able to work at ultra high speed by utilizing boundary slip is investigated. Due to the applied prospect of silicon carbide in the field of MEMS especially under high temperature and high strength conditions, the technical process of combining silicon etching with reactive sintering and grinding machining of silicon carbide is put forward so that the miniature machining of silicon carbide for micro gas turbine engine becomes possible.     

New Technology of Profile Grindng for Tow Teeth Difference Cyclodal Gear

Two teeth diffenence cyclodal gears are the key parts in cyclodal reducer. The plate abrasive wheel method which is widely used at home has very low precision and productivity. So it' s the common problem to be immediately solved. The profile grinding technology discussed in this paper has been proved by practical production to be an efficient and economical cycodal gear manufacturing method.     

大枣加工工艺及设备的应用研究

通过对大枣保鲜、加工工艺,以及其加工设备的分析,提出了朝阳市大枣加工企业在确定其产品结构及设备选择等方面的建议。     

打造现代规模化粮食产业示范基地的技术对策研究

建设大型现代粮食示范基地是促进粮食产业和确保粮食安全的重要举措,本文旨为全国新增500亿kg粮食生产能力建设提供借鉴和参考。采用文献调查与实地调查、定性与定量相结合的方法,在分析了四川粮食生产存在的主要问题的基础上,提出科技支撑现代粮食产业示范基地建设的技术对策。稻麦两熟是四川粮食生产最主要形式,在稻麦两熟区建立现代粮食示范基地具有重要意义。其主要技术对策是开展稻麦专用新品种引进筛选,稻麦丰产高效生产技术、稻田周年高效种植模式、粮食规模化干燥与加工技术集成与示范以及新型科技成果转化服务机制探索等。最后,分析了科技支撑基地建设的经济效益、社会效益、生态效益和产业化前景。农业科技在现代粮食产业示范基地中大有作为,并要突出规范化、集约化、标准化和产业化。     

发展现代农业对农业科学技术自主创新的要求与任务

简要阐述了中国发展现代农业的基本任务,分析了发展现代农业对农业科学技术自主创新的要求,提出了发展农业科学技术的目标、任务和优先领域,重点对种质资源创新与遗传改良、农业资源高效利用、优质高产安全高效生产、重大农业生物灾害防控制、农业环境控制与修复、特色农业生产、工厂化农业、现代设施与装备、农业信息与市场服务、农产品深加工、农业质量与标准、绿色农业生物制品、工业原料生产、农村新能源与社区环境建设、小城镇建设与新材料等研究重点进行了探讨     

山西现代农业科技创新体系问题与建设研究

加快山西省现代农业的跨越发展,突破资源、环境和经济的约束,必须以农业科技为根本出路,以现代农业科技创新体系为支撑。笔者分析了现阶段山西现代农业科技创新体系中的薄弱环节,阐述了新时期山西现代农业科技创新体系建设的内容,并对加快建设山西现代农业科技创新体系提出了建议。     

生态技术在现代农业中的地位及其技术群构成

提出了现代农业的主要支撑技术包括生态技术、生物技术和管理技术,并分析了此三类支撑技术的相互关系;通过深入比较,指出生态技术在现代农业中应占主导地位,这是现代农业发展的内在要求,是中国生态环境现状的必然选择,是建立社会主义和谐社会的必然趋势;同时提出了生态技术群中应该重点发展的主要技术:立体农业技术、综合养殖生态技术、特色农业技术、多色农业技术、设施农业技术、农业综合节水技术、农业污染综合防治技术和无公害绿色农产品标准化生产技术等。     

川贝雪梨脆片变温压差膨化干燥应用技术

以雪梨为主要原料,配以川贝母、百合、甘草等药典成方药食同源中药熏蒸,强化雪梨产品的食疗功效;在生产过程中利用真空膨化干燥设备,应用变温压差膨化干燥技术,形成了较完善的川贝雪梨脆片变温压差膨化干燥技术工艺。     

科技创新与现代农业建设

阐述与探讨了科技创新在现代农业建设中的作用,研究如何通过科技的创新与进步推动现代农业的发展。通过研究,发现中国在科技进步推动现代农业建设中存在有创新供给不足。农户文化素质低,经营规模小,对现代农业认识不足且科技与农户、企业间缺乏推广、中介机制。针对存在的不足,需通过科技创新体系改革,建立农业科技推广服务与中介机制,培育龙头企业,加强教育,提高农民科技文化素质等措施定位,加快现代科技农业建设。     

关于我国现代农业采后科技创新与发展对策的思考

为发展我国现代农业,提升采后科技创新能力,本文提出了我国现代农业采后科技创新与发展对策,主要包括：产学研结合,加快农产品采后科技创新步伐;选准方向,加强共性技术攻关,解决产业化关键技术;加强农产品保鲜国内外技术交流与合作,加快与国际接轨的步伐等。     

黑豆面包的研制及其质构特性的研究

通过向面粉中添加不同比例的黑豆粉,利用质构仪测定在不同储藏时间下,面包质构特性的变化趋势,发现添加5%黑豆粉末的面包,在硬度、弹性、咀嚼性3个方面都有很好改善,不但增强了面包的营养价值,而且还具有良好的保藏性能,使货架期更长。     

低糖颗粒型草莓酱的研制与工业化生产的探讨

以草莓为原料,采用二次真空渗糖与复合增稠剂调配相结合的方法,进行了低糖草莓酱的研制,并探讨了草莓酱工业化生产的问题。结果显示,低糖草莓酱的可溶性固形物含量大于25%,糖度为25%左右,pH值为3.0,产品色泽自然,滋味宜人。