【摘要】：裝載機(jī)是工程機(jī)械中廣泛使用的機(jī)種，在工程建設(shè)項(xiàng)目中發(fā)揮著重要的作用。轉(zhuǎn)向系統(tǒng)是裝載機(jī)重要的子系統(tǒng)之一，轉(zhuǎn)向系統(tǒng)的性能好壞直接關(guān)系到裝載機(jī)的安全可靠性，因此對(duì)于轉(zhuǎn)向系統(tǒng)的研究工作具有重要的意義。以往對(duì)于轉(zhuǎn)向系統(tǒng)的研究大多基于系統(tǒng)的數(shù)學(xué)模型，對(duì)于元件及負(fù)載都進(jìn)行了多種簡(jiǎn)化和等效，特別是對(duì)于轉(zhuǎn)向系統(tǒng)的負(fù)載無(wú)法建立準(zhǔn)確的模型�；诖�，本文結(jié)合校企合作項(xiàng)目“裝載機(jī)液壓系統(tǒng)及傳動(dòng)系統(tǒng)動(dòng)態(tài)仿真分析及對(duì)比測(cè)試研究”，以鉸接式裝載機(jī)的負(fù)荷傳感全液壓轉(zhuǎn)向系統(tǒng)為研究對(duì)象，采用機(jī)液聯(lián)合仿真的方法對(duì)轉(zhuǎn)向系統(tǒng)的動(dòng)態(tài)特性進(jìn)行了分析研究。 本文根據(jù)優(yōu)先閥、轉(zhuǎn)向器的實(shí)際結(jié)構(gòu)，詳細(xì)分析了轉(zhuǎn)向系統(tǒng)兩大關(guān)鍵元件的工作原理，通過(guò)對(duì)優(yōu)先閥和轉(zhuǎn)向器建立靜態(tài)數(shù)學(xué)模型，分析了二者的靜態(tài)特性；同時(shí)，對(duì)輪胎進(jìn)行了相關(guān)的理論分析。在此基礎(chǔ)上，利用AMESim軟件建立了優(yōu)先閥和轉(zhuǎn)向器的仿真模型，其中對(duì)轉(zhuǎn)向器提出一種全新的建模方式，可以充分體現(xiàn)轉(zhuǎn)向器的實(shí)際結(jié)構(gòu)并保證其位移控制隨動(dòng)功能，進(jìn)而很好地反映其原理性能。根據(jù)不同工況，對(duì)轉(zhuǎn)向系統(tǒng)進(jìn)行了動(dòng)態(tài)仿真分析，通過(guò)仿真發(fā)現(xiàn)兩個(gè)轉(zhuǎn)向油缸的運(yùn)動(dòng)有一定區(qū)別，其中轉(zhuǎn)向同側(cè)的油缸運(yùn)動(dòng)速度稍快，活塞桿位移較大，指出一直以來(lái)的誤區(qū)，為以后的設(shè)計(jì)工作提供了參考。通過(guò)鉸接式裝載機(jī)的轉(zhuǎn)向系統(tǒng)實(shí)驗(yàn)，驗(yàn)證了仿真模型的正確性，，并分析了系統(tǒng)的動(dòng)態(tài)性能。 鑒于一直以來(lái)對(duì)于轉(zhuǎn)向系統(tǒng)負(fù)載等效的困難，本文通過(guò)多體動(dòng)力學(xué)仿真軟件LMS Virtual.Lab Motion建立了鉸接式裝載機(jī)的動(dòng)力學(xué)仿真模型，充分考慮了轉(zhuǎn)向機(jī)構(gòu)和輪胎與地面作用對(duì)轉(zhuǎn)向的影響，并與AMESim進(jìn)行機(jī)液聯(lián)合仿真，通過(guò)與實(shí)驗(yàn)的對(duì)比證明，聯(lián)合仿真結(jié)果與實(shí)驗(yàn)結(jié)果比較接近，可以很好地反映實(shí)際情況，從而為轉(zhuǎn)向系統(tǒng)的負(fù)載模擬開(kāi)辟了一種新的途徑。同時(shí)，通過(guò)對(duì)不同工況的聯(lián)合仿真，分析了轉(zhuǎn)向過(guò)程中輪胎的受力情況及其對(duì)系統(tǒng)壓力的影響，并發(fā)現(xiàn)適當(dāng)減小輪胎的側(cè)偏剛度有利于減小轉(zhuǎn)向的壓力振擺現(xiàn)象，為以后的研究工作提供了參考。
[Abstract]:Loader is widely used in construction machinery and plays an important role in engineering construction projects. Steering system is one of the important subsystems of loader. the performance of steering system is directly related to the safety and reliability of loaders, so it is of great significance to the research work of steering system. In the past, most of the research on steering system is based on the mathematical model of the system, and many kinds of simplification and equivalence have been carried out for the components and loads, especially for the load of the steering system, it is impossible to establish an accurate model. Based on this, combined with the cooperation project between school and enterprise, "dynamic simulation analysis and comparative test research of hydraulic system and transmission system of loader", this paper takes the load sensing full hydraulic steering system of hinged loader as the research object. The dynamic characteristics of steering system are analyzed and studied by using the method of machine-liquid joint simulation. In this paper, according to the actual structure of priority valve and steering gear, the working principle of two key components of steering system is analyzed in detail, and the static characteristics of priority valve and steering gear are analyzed by establishing static mathematical model of priority valve and steering gear. At the same time, the related theoretical analysis of tire is carried out. On this basis, the simulation model of priority valve and steering gear is established by using AMESim software, in which a new modeling method is proposed for steering gear, which can fully reflect the actual structure of steering gear and ensure its displacement control follow-up function. Then it reflects its principle and performance very well. According to different working conditions, the dynamic simulation analysis of the steering system is carried out. Through the simulation, it is found that there are some differences in the motion of the two steering cylinders, in which the moving speed of the steering cylinder on the same side is slightly faster and the displacement of the piston rod is larger, pointing out the misunderstanding for a long time. It provides a reference for the future design work. The correctness of the simulation model is verified by the steering system experiment of the hinged loader, and the dynamic performance of the system is analyzed. In view of the difficulty of load equivalence for steering system, the dynamic simulation model of hinged loader is established by using multi-body dynamics simulation software LMS Virtual.Lab Motion. The influence of steering mechanism and tire and ground action on steering is fully considered, and the joint simulation with AMESim is carried out. the comparison with the experiment shows that the joint simulation results are close to the experimental results and can reflect the actual situation very well. Thus, a new way for load simulation of steering system is opened up. At the same time, through the joint simulation of different working conditions, the stress of the tire and its influence on the system pressure during the steering process are analyzed, and it is found that the proper reduction of the lateral stiffness of the tire is beneficial to reduce the pressure pendulum phenomenon of the steering. It provides a reference for the future research work.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2012
【分類(lèi)號(hào)】：TH243

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 呂傳祥;具有2DOF鉸接車(chē)體挖掘機(jī)工作裝置液壓系統(tǒng)仿真與實(shí)驗(yàn)研究[D];吉林大學(xué);2013年

本文編號(hào)：2485434