1、 毕业论文 (设计 )外文翻译 机械工程 学院 机械制造及其自动化 专业 (本 科 )2008 级 机制二 班 课题名称:某变速箱上盖零件大批生产的 工艺工装设计 毕业论文 (设计 )起止时间: 2012 年 03 月 05 日 05 月 25 日 (共 12 周 ) 学生姓名: 学号: 2008111204 指导教师: 报告日期: 2012.03.17 THE RESEARCHS OF AMT SHIFTING SCHEDULES Vehicular Automatic Transmission can be divided into three types: Automatic Trans
2、mission (AT), Automated Mechanical Transmission (AMT) and Continuously Variable Transmission (CVT). AMT has become a kind of transmission that is full of potentiality, due to its high transfer efficiency, low cost and easiness to manufacture. The research on AMT shifting performance is key technolog
3、y in the developing. Shifting performance directly influence the market competition and industrialization of AMT. AMT has good market expectation, but during the shifting procedure, the power must be cut off which causes the poor shifting performance than AT and CVT. Only through improving the shift
4、ing performance can the commercial competence be established. So the virtual important thing is to find the way to improve shifting performance. The development of AMT can be divided into three phases: semi-automatic, automatic and intelligent. The two major part of AMT are: the hardware including t
5、he mastered object, executor, sensors and TCU; and the software performing the control strategy. The performance of AT shift influences greatly the performance of the vehicle. So the research on at shift quality is an important problem in the domain of AT researching. Shift quality control of AT is
6、accomplished by electronic and hydraulic system. To shift smoothly, according the real time throttle valve opening and vehicle speed signal, the controller sends electronic signals to control oil pressure changing curve of the applying elements. this paper analyzes and research detailed shift qualit
7、y control system, the analyzing model of shifting process and pressure changing curve of the applying elements Firstly this paper summarizes the existing evaluated quota of shift quality, and fully analyzes and introduces the existing control manner of AT shift quality. To meet the needs of research
8、 of vehicle starting and the real time control of shift, this paper puts forward a simplified model of engine-torque and a dynamics model of AT shifting process. Through the applying of the established model, this paper fully analyzes the process of the AT shifting. This paper drafts the proper oil
9、pressure changing curve of the applying elements which can improve the AT shift quality, and gives the material calculated methods of the AG4 AT. This paper simulates the AG4 ATs shifting process of 2H to 3H.The results of the simulation validate the established simplified models and the expected oi
10、l pressure changing curve. This paper fully analyzes the mechanism of the pressure regulating and flow controlling system of the AG4 AT, and preparatory discusses the design of the block-diagram of the shift quality control. This paper test the control system and hydraulic system of the AG4 AT by th
11、e AT hydraulic-electronic testing-bed. The result of the test validates the correction of these analyses. Automated Mechanical Transmission, as so called AMT, is a new-style transmission system. AMT technology applies the automatic technology to the manual mechanical transmission and makes the selec
12、tion-gear, shift, clutch and throttle implement automatically. AMT technology is suitable for the situation of our country, and has an expansive market and development foreground. Shift schedules decide the time to shift and are the soul of the AMT. When the AMT is working, by comparing the states o
13、f the vehicle with the optimal shift schedules, the AMT decides the optimal shift time and achieves the shift automatically. This will lessen the tiredness of the driver and improve the safety. At the same time, the power and fuel-economy of the vehicle can also be improved. The author chooses the s
14、hift schedule as the key technology problem to be researched and the main study aim of this thesis is to get the optimal shift schedules for the AMT and so improve the power and fuel-economy of the vehicle. Through analyzing the influence factors of power and fuel-economy for the automobile, the aut
15、hor get the establishment methods for the optimal-power shift schedule and optimal fuel-economy shift schedule. In order to solve the influence of mass on the shift schedule, the author presents a variable-structure-controlled shift system. This enriches the theory of shift schedules. Because the co
16、mputer simulation can save a lot of manpower and material resources comparing with the true-car test, so in this thesis, the author uses the simulation toolbox MATLAB/Simulate to setup the simulation model for shift schedules. Using this model, the optimal-power shift schedule and optimal fuel-econo
17、my shift schedule above are simulated and proved to be reasonable. Shifting performance is defined as the extent of swiftness and softness during the procedure of non-power shifting and to extend the life of the power train. The index is comfort of passenger, time duration and shock, nine factors ma
18、ybe influence the shifting performance, and two experimental methods can be used to investigate the nature of this performance: one is collecting real-time data during road experiment and analyzing them, the other is the simulation of the operation conditions of the vehicle. The core of the AMT syst
19、em is the control strategy, the principle of the clutch engagement, shifting procedure, the choice of control method and the CAN communication between TCU and ECU can influence the shifting performance. Shifting schedule is the schedule of auto shifting time between two shifts with controlling param
20、eters. It includes economical and dynamical shifting schedule. At present, shifting schedule of two controlling parameters (vehicle speed and opening on throttle) is mainly used. If shifting schedule is not good, shifting will not happen at right time and the working condition of engine will be seve
21、re. It will make the sound of engine abnormally and stability badly through the whole shifting procession. Sometimes even flame out Schedule of clutch engagement is determined by releasing journey of clutch, opening of throttle, shifting, vehicle speed and loading. The main Controlling goals are eng
22、aging quantity and engaging speed. The engaging control of clutch is mainly referred to the control of engaging speed. It is divided into three stages: fast, slow, fast. Shifting quality is directly influenced by the second stage. If engaging harder, it will make shifting concussion, even flame out;
23、 if engaging more slowly, it will make the friction time longer and reduce its longevity. The main controlling parameters are difference between initiative and passive and torques on both sides. When torques being approximately equal, it is proved by experiments that it can guarantee shifting time a
24、nd not make concussion through the procession of engagement at the time of difference of rotating speed below some value. Meanwhile, the abrasion of clutch is not severe. Shifting procedure is the procedure through working harmoniously among engine, clutch and transmission. Their cooperation will affect shifting time heavily. In order to decrease the shifting time, the time that is spent on the friction of the clutch should be decreased first. If we intend to increase the time of non-load stage, which helps to minimize the difference of the rotary speed