检索结果-南通市图书馆

STUDY ON SHIFT SCHEDULE AND SIMULATION OF AUTOMATIC TRANSMISSION

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2001年第3期14卷 250-253页

作者： Gong Jie,Zhao Dingxuan (College of mechanical science and engineering ,Jilin University) 吉林大学机械科学与工程学院吉林长春

From the point of view of saving energy, a new shift schedule and auto-controlling strategy for automatic transmission are proposed. In order to verify this shift schedule, a simulation program using a software package of Matlab/ Simulink is developed. The simulation results show the shift schedule is correct. This shift schedule has enriched the theory of vehicle automatic maneuvering and will improve the efficiency of hydrodynanic drive system of the vehicle.

关键词： engineering vehicle Automatic transmission Shift schedule Simulation Saving energy

WORK PRINCIPLE AND CHARACTERISTIC ANALYSES OF HYDROSTATIC BEARING

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第2期15卷 162-166页

作者： Nie Songlin Li ZhuangyunSchool of mechanical science and engineering, Huazhong University of science and TechnologyWuhan 430074, China School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074

Aiming at the new characteristic of water hydraulic system, a kind ofhydrostatic bearing with a concentric gap damper is introduced. The lubricative film thickness ofthe hydrostatic bearing possesses inflexibility and the loading capacity is just determined by thegeometrical dimension of the piston-slipper subassembly and has no relation with system pressure,viscosity and temperature of water and speed of rotor. Theoretical analyses and the verification ofscheme done at the test rig show that the hydrostatic bearing with a concentric gap damper isespecially fit for water hydraulic components.

关键词： Hydrostatic bearing Concentric gap Water lubricity Water hydraulicmotor

PROFILE TOLERANCE EVALUATION OF PARAMETRIC CURVES AND SURFACES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第2期15卷 121-125页

作者： Huang Xiaoping Xiong YoulunSchool of mechanical science and engineering, Huazhong University of science and Technology,Wuhan 430074, China School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China ***

The profile error evaluation of complex curves and surfaces expressed inparametric form is considered. The linear error model is established on the base of two hypothesesfirstly. Then the profile error evaluation is converted into one of these optimal formulations:MINIMAX, MAXMIN and MINIDEX problems, which are easier to be solved than the initial form. To eachone of them, geometric condition and algebraic condition are presented to arbitrate whether theideal element reaches to the optimal position. Exchange algorithm is proven highly effective insearching for solutions to these optimization problems. At last some key problems in tolerance offreeform surfaces and curves in B spline method are discussed.

关键词： Parametric form Profile tolerance Linear error model Exchangealgorithm

INTEGRATED APPROACH TO GENERATION OF PRECEDENCE RELATIONS AND PRECEDENCE GRAPHS FOR ASSEMBLY SEQUENCE PLANNING

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第3期15卷 193-198页

作者： Niu Xinwen Ding Han Xiong YoulunSchool of mechanical science and engineering, Huazhong University of science and TechnologyWuhan 430074, China *** School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China

An integrated approach to generation of precedence relations and precedencegraphs for assembly sequence planning is presented, which contains more assembly flexibility. Theapproach involves two stages. Based on the assembly model, the components in the assembly can bedivided into partially constrained components and completely con-strained components in the firststage, and then geometric precedence relation for every component is generated *** to the result of the first stage, the second stage determines and constructs allprecedence graphs. The algorithms of these two stages proposed are verified by two assemblyexamples.

关键词： Assembly sequence planning Assembly flexibility Precedence relations Precedence graphs

OPTIMAL FEED RATE CONTROL FOR MULTI-AXIS CNC MACHINING OF FREE FORM SURFACES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2000年第3期13卷 171-177页

作者： Zhan Yong, Zhou Ji, Zhou Yanhong, Zhou Yunfei (School of mechanical science and engineering, Huazhong University of science and Technology) 华中科技大学湖北武汉

Considering machining efficiency, surface quality and wear of cutter and machine, it is necessary to maintain high, stable and constant surface feed rate as far as *** feed late control strategy for multi-axis CNC machining of free-form surfaces is presented. It comprises: ①the determination of effective feed rate; ②the adoption of suitable approaches to smooth feed rate. This strategy considers path geometry, actuator limitation and machine dynamics. The result shows that machining efficiency is improved effectively.

关键词： CNC Surface machining Feed rate Multi-axisp

EXPERIMENTAL STUDY ON TRIBOLOGICAL PROPERTIES OF FULLERENE COPOLYMER NANOBALL

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2000年第3期13卷 201-205页

作者： Lei Hong (School of mechanical science and engineering, Huazhong University of science and Technology) Guan Wenchao, Liao Daoxun (Huazhong University of science and Technology) 华中科技大学湖北武汉

A novel fullerene-styrene-maleic anhydride copolymer is reported. TEM analyses shows it is water- soluble nanoball of average diameter of about 83 nm. The tribological behavior is evaluated by foul-ball machine. It was found that addition of fullerene copolymer to base stock (2%triethanolamine aqueous solution)resulted in a raise in load-carrying ability(F value)from 130 N to maximum 480 N, and a reduction in coefficient of friction from 0.235 to minimum 0. 063. SEM analyses indicates that the wear scare obtained with fullerene copolymer exhibited mild scratches, while sharp grooving and serious pull-out phenomnon were observed in the presence of base stock without additive .The improvements in friction, wear and load-carrying capacity are probably due to the presence of fullerene copolymer nanoballs, which may act as molecule ball bearings, which in turn lead to elastic rolling lubrication.

关键词： Water-soluble Fullerene copolymer Nanoball Fricition and wear Microcosmic elastic rolling8

MODELING AND IMPLEMENTATION OF A DISTRIBUTED SHOP FLOOR MANAGEMENT AND CONTROL SYSTEM

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第3期15卷 213-217页

作者： Liu Shiping Rao Yunqing Zhang Jie Li PeigenSchool of mechanical science and engineering, Huazhong University of science and Technology,Wuhan 430074, China School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074

Adopting distributed control architecture is the important developmentdirection for shop floor management and control system, is also the requirement of making it agile,intelligent and concurrent. Some key problems in achieving distributed control architecture areresearched. An activity model of shop floor is presented as the requirement definition of theprototype system. The multi-agent based software architecture is constructed. How the core part inshop floor management and control system, production plan and scheduling is achieved. Thecooperation of different agents is illustrated. Finally, the implementation of the prototype systemis narrated.

关键词： Agent Shop floor management and control CIMS

CLASSIFICATION OF GEAR FAULTS USING HIGHER-ORDER STATISTICS AND SUPPORT VECTOR MACHINES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第3期15卷 243-247页

作者： Lai Wuxing Zhang Guicai Shi Tielin Yang ShuziSchool of mechanical science and engineering, Huazhong University of science and Technology,Wuhan 430074, China *** School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China

Gears alternately mesh and detach in driving process, and then workingconditions of gears are alternately changing, so they are easy to be spalled and worn. But becauseof the effect of additive gaussian measurement noises, the signal-to-noises ratio is low; theirfault features are difficult to extract. This study aims to propose an approach of gear faultsclassification, using the cumulants and support vector machines. The cumulants can eliminate theadditive gaussian noises, boost the signal-to-noises ratio. Generalisation of support vectormachines as classifier, which is employed structural risk minimisation principle, is superior tothat of conventional neural networks, which is employed traditional empirical risk minimisationprinciple. Support vector machines as the classifier, and the third and fourth order cumulants asinput, gears faults are successfully recognized. The experimental results show that the method offault classification combining cumulants with support vector machines is very effective.

关键词： Support vector machine Gear Fault diagnosis Cumulant Featureextraction

CAD/CAE OF THE WORKING CHARACTERISTICS OF A NEW TYPE OF FLUID COUPLING SHOCK ABSORBER

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of mechanical engineering 2002年第3期15卷 222-227页

作者： Yang Ping Zhong Yifang Zhou JiSchool of mechanical science and engineering, Huazhong University of science and Technology,Wuhan 430074, ChinaLiu Yong Guilin Institute of Electronic Technology *** School of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China

For purpose of simulation of the working characteristics of a new type offluid coupling shock absorber for vibration protection of sensitive equipment, a physical model ispresented by analyzing the internal fluid dynamic phenomenon with respect to the coupling shockabsorber and implemented in MATLAB software package. Using the model it is possible to evaluate theimportance of different factors for design of the shock absorber. In the meantime, the key-modelmachine is designed for coupling dynamic test. Comparisons with experimental results confirm thevalidity of the model. So the CAD/CAE software has been developed in MATLAB for design andexperimental test of the new coupling shock absorber.

关键词： Fluid coupling shock absorber Working characteristics Model Simulation