液压机械无级变速器的设计及特性研究

发布时间：2018-11-05 08:03

【摘要】：变速箱作为车辆的核心部分,其输出特性对车辆的作业品质有着直接的影响。液压机械无级变速器具有传动比连续可调、动力传递平稳、操纵方便,燃油经济性高的优点。目前,我区对自走式农业机械液压机械无级变速器的研究还很薄弱,开展对液压机械无级变速器的研究,不但可为我区自走式农业机械变速箱所面对的诸多技术难题提供新思路,还可为我区研究无级变速技术提供理论参考。本文是以设计开发一种新型液压机械无级变速器为目标,主要研究内容如下:(1)基于对定轴齿轮副分流和汇流、行星齿轮副分流和汇流形式和特性的研究,确定了采用分矩汇速型作为液压机械无级变速器分、汇流组合方案;建立了液压机械无级变速多区段等差传动条件下、等比传动条件下、连续传动下的理论模型;设计开发了具有自主知识产权的采用“变量泵+定量马达”和双排行星齿轮副相组合的分矩汇速型等差多段式液压机械无级变速传动方案;(2)基于对液压机械无级变速器传动方案的优化设计,确定了液压机械无级变速器的换段方式及各段的换段逻辑,并绘制了各区段液压机械无级变速器动力传递路线;针对所优选的设计方案,建立了液压机械无级变速器各区段输出转速的理论模型;结合变速箱的传动匹配设计以及整机田间作业特性,确定了液压系统特性的参数;在满足液压机械无级变速器的总传动比、各区段连续换段、各区段等差传动、液压系统元件要求的前提下完成了液压机械无级变速器的参数设计;着重分析了各区段传动比随排量比变化特性、行驶速度随排量比变化特性、变速器扭矩特性、液压功率分流比等特性;研究表明,该方案满足了液压机械无级变速器的连续无级变速要求;(3)针对行星齿轮副太阳轮、行星架和齿圈均处于回转运动的工况,创新设计了两种双排行星齿轮副支撑机构以加强双排行星齿轮副运转的稳定性;与支撑机构相对应设计了两种双排行星齿轮副结构形式;分别设计了液压机械无级变速轴、箱体、整机等结构;利用三维软件建模软件完成液压机械无级变速器样机三维建模,完成了液压机械无级变速器的整套产品图纸的绘制,最终完成液压机械无级变速器实验样机的加工制造;(4)提出了液压机械无级变速器实验台总体功能要求;完成液压机械无级变速器实验台整体结构布局,并搭建了实验平台机械部分结构;搭建了液压机械无级变速器试验平台离合器液压系统、泵控马达系统液压油路;提出了试验平台测控系统的数据采集与控制系统功能要求;初步搭建完成液压机械无级变速器试验台,验证了液压机械无级变速器的连续性。
[Abstract]:As the core part of the vehicle, the output characteristics of the gearbox have a direct impact on the working quality of the vehicle. Hydraulic mechanical stepless transmission has the advantages of continuously adjustable transmission ratio, stable power transmission, convenient operation and high fuel economy. At present, the research on the stepless transmission of self-propelled agricultural machinery hydraulic machinery in our region is still very weak, and the research on the stepless transmission of hydraulic machinery has been carried out. It can not only provide new ideas for many technical problems of self-propelled agricultural machinery gearbox, but also provide a theoretical reference for the study of stepless transmission technology in our region. The main contents of this paper are as follows: (1) based on the research of the distribution and confluence of the fixed axis gear pair, the form and characteristics of the planetary gear pair shunt and confluence. The combined scheme of dividing moment and confluence speed is determined as the continuous variable transmission of hydraulic machinery. The theoretical model of continuous transmission is established under the condition of constant speed and multi-section constant differential transmission of hydraulic machinery and the condition of equal ratio transmission. This paper designs and develops a variable pump quantitative motor with independent intellectual property rights and a multi-segment stepless transmission scheme of torque converging speed type and isodyne multi-segment hydraulic machinery using the combination of "variable pump quantitative motor" and double-row planetary gear pair. (2) based on the optimal design of the transmission scheme of the hydraulic machinery stepless transmission, the changing mode of the hydraulic machinery stepless transmission and the logic of each segment are determined, and the power transmission route of the hydraulic machinery stepless transmission is drawn. According to the selected design scheme, the theoretical model of output speed of every section of hydraulic mechanical stepless transmission is established, and the parameters of hydraulic system characteristic are determined according to the transmission matching design of gearbox and the field operation characteristics of the whole machine. The parameter design of hydraulic mechanical stepless transmission is completed on the premise of satisfying the total transmission ratio of hydraulic mechanical stepless transmission, continuous changing section of each section, equidifferential transmission of each section, and the requirement of hydraulic system components. The variation characteristics of transmission ratio with displacement ratio, speed with displacement ratio, transmission torque characteristic and hydraulic power shunt ratio are analyzed emphatically. The research shows that the scheme can meet the requirement of continuous stepless speed change of hydraulic machinery stepless transmission. (3) two kinds of double row planetary gear pair supporting mechanism are designed to enhance the stability of the double row planetary gear pair in view of the solar gear of the planetary gear pair, the planetary rack and the gear ring are in the condition of rotary motion; Two kinds of double row planetary gear pair structures are designed corresponding to the supporting mechanism, hydraulic machinery stepless variable shaft, box, whole machine and other structures are designed respectively. The 3D modeling software is used to complete the 3D modeling of the hydraulic machinery CVT prototype, and the drawing of the whole product drawing of the hydraulic machinery CVT is completed. Finally, the machining and manufacturing of the hydraulic machinery CVT experimental prototype is completed. (4) the overall functional requirements of the hydraulic mechanical stepless transmission experimental platform are put forward, the overall structure layout of the hydraulic machinery stepless transmission experimental platform is completed, and the mechanical part structure of the experimental platform is built. The hydraulic system of clutch and pump control motor system is built, and the functional requirements of data acquisition and control system of test platform are put forward. The hydraulic mechanical stepless transmission test bench was built to verify the continuity of the hydraulic mechanical stepless transmission.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U463.221

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