A new type continuous variable transmission device, a hydro-mechanical continuously variable transmission （HMCVT） for agricultural tractors is developed, which is composed of a single planetary gear differential tra...A new type continuous variable transmission device, a hydro-mechanical continuously variable transmission （HMCVT） for agricultural tractors is developed, which is composed of a single planetary gear differential train, a hydraulic transmission system consisted of variable displacement pump and fixed displacement motor and a multi-gear fixed step radio transmission. Based on the analysis of types of hydrostatic mechanical transmission （HMT） and styles of hydraulic transmission, the general drive scheme for HMCVT is obtained. The method of selecting mechanical parameters and hydraulic units is explained, and the stepless speed regulation characteristic of HMCVT is analyzed. This paper also specializes the calculating method of transmission efficiency. It shows that tractors assembled with HMCVT can obtain a continuously variable speed and achieve high drive efficiency.展开更多
In order to reduce the driving fatigue in sowing work, this paper based on heart rate （HR） as the main indicator to survey, tested and analyzed the fatigue condition of the drivers of three imported tractors and one...In order to reduce the driving fatigue in sowing work, this paper based on heart rate （HR） as the main indicator to survey, tested and analyzed the fatigue condition of the drivers of three imported tractors and one domestic tractor in sowing work. The results showed that when driving the imported tractors in sowing work, the HR increasing rate was 10.4%-14.3%, labor intensity belonged to the light level; when driving domestic tractor in sowing work, the HR increasing rate was 23.4%-33.0%, it was remarkably bigger than that of driving imported tractors （P〈0.05）, labor intensity belonged to the middle level. The main effects on driving fatigue included the control methods, tractors＇ cab environment, processing time, operating content, and so on. Finally, we proposed the concrete measures and suggestions to reduce driving fatigue and improve drivers＇ work condition.展开更多
For further understanding reliability and serviceability of tractor and to furnish scientific and technical theories, based on the promotion and application of it, the following experiments and statistical analysis on...For further understanding reliability and serviceability of tractor and to furnish scientific and technical theories, based on the promotion and application of it, the following experiments and statistical analysis on reliability （reliability and MTBF） serviceability （service and MTTR） of Donfanghong-1002 and Dongfanghong-802 were conducted. The result showed that the intervals of average troubles of these two tractors were 182.62 h and 160.2 h, respectively, and the weakest assembly of them was engine part.展开更多
Based on dynamic analysis for the Front Wheel Assist (FWA) tractor, a calculating and analysing method on selecting the optimum coefficient of inharmonious motion for the FWA tractor is described in this paper and the...Based on dynamic analysis for the Front Wheel Assist (FWA) tractor, a calculating and analysing method on selecting the optimum coefficient of inharmonious motion for the FWA tractor is described in this paper and the mathematical models arc also established. The article first time dlefines the ratio of thrust of front wheels to that of rear wheels, which is an important parameter affecting the tractive performance of the FWA tractor and establishes the condition of no power circulation of the FWA tractor. The optimum coefficient of inharmonious motion for a FWA tractor (UTB-445) is also given.展开更多
Base on dynamic analysis for a Front Wheel Assist (FWA) tractor, a method of calculating and analyzing on the critical angle of steering for a FWA tractor is described in this paper. The mathematical model is also est...Base on dynamic analysis for a Front Wheel Assist (FWA) tractor, a method of calculating and analyzing on the critical angle of steering for a FWA tractor is described in this paper. The mathematical model is also established here. The critical steering angle which is a important parameter affecting the steering performance for a FWA tractor is defined in the article.展开更多
Based on dynamic analysis of Front wheel Assist (FWA) Tractor,a method for calculating the thrust Ratio of front wheels to rear wheels is described in this paper,a mathematical model is established and verified,The ar...Based on dynamic analysis of Front wheel Assist (FWA) Tractor,a method for calculating the thrust Ratio of front wheels to rear wheels is described in this paper,a mathematical model is established and verified,The article introduces the definition of thrust ratio of front wheels to rear wheels,which is an important parameter affecting the tractive performance of FWA tractor.展开更多
基金Fund of Henan Innovation Project for University Prominent Research Talents (2002KYCX010) Youth Scientific Research Foundation of Henan University of Science and Technology (2004QN030)
文摘A new type continuous variable transmission device, a hydro-mechanical continuously variable transmission （HMCVT） for agricultural tractors is developed, which is composed of a single planetary gear differential train, a hydraulic transmission system consisted of variable displacement pump and fixed displacement motor and a multi-gear fixed step radio transmission. Based on the analysis of types of hydrostatic mechanical transmission （HMT） and styles of hydraulic transmission, the general drive scheme for HMCVT is obtained. The method of selecting mechanical parameters and hydraulic units is explained, and the stepless speed regulation characteristic of HMCVT is analyzed. This paper also specializes the calculating method of transmission efficiency. It shows that tractors assembled with HMCVT can obtain a continuously variable speed and achieve high drive efficiency.
基金"211" Talent Start-up Fund Project of Northeast Agricultural University (183)
文摘In order to reduce the driving fatigue in sowing work, this paper based on heart rate （HR） as the main indicator to survey, tested and analyzed the fatigue condition of the drivers of three imported tractors and one domestic tractor in sowing work. The results showed that when driving the imported tractors in sowing work, the HR increasing rate was 10.4%-14.3%, labor intensity belonged to the light level; when driving domestic tractor in sowing work, the HR increasing rate was 23.4%-33.0%, it was remarkably bigger than that of driving imported tractors （P〈0.05）, labor intensity belonged to the middle level. The main effects on driving fatigue included the control methods, tractors＇ cab environment, processing time, operating content, and so on. Finally, we proposed the concrete measures and suggestions to reduce driving fatigue and improve drivers＇ work condition.
基金Supported by Education Department of Heilongjiang Province (9551022)
文摘For further understanding reliability and serviceability of tractor and to furnish scientific and technical theories, based on the promotion and application of it, the following experiments and statistical analysis on reliability （reliability and MTBF） serviceability （service and MTTR） of Donfanghong-1002 and Dongfanghong-802 were conducted. The result showed that the intervals of average troubles of these two tractors were 182.62 h and 160.2 h, respectively, and the weakest assembly of them was engine part.
文摘Based on dynamic analysis for the Front Wheel Assist (FWA) tractor, a calculating and analysing method on selecting the optimum coefficient of inharmonious motion for the FWA tractor is described in this paper and the mathematical models arc also established. The article first time dlefines the ratio of thrust of front wheels to that of rear wheels, which is an important parameter affecting the tractive performance of the FWA tractor and establishes the condition of no power circulation of the FWA tractor. The optimum coefficient of inharmonious motion for a FWA tractor (UTB-445) is also given.
文摘Base on dynamic analysis for a Front Wheel Assist (FWA) tractor, a method of calculating and analyzing on the critical angle of steering for a FWA tractor is described in this paper. The mathematical model is also established here. The critical steering angle which is a important parameter affecting the steering performance for a FWA tractor is defined in the article.
文摘Based on dynamic analysis of Front wheel Assist (FWA) Tractor,a method for calculating the thrust Ratio of front wheels to rear wheels is described in this paper,a mathematical model is established and verified,The article introduces the definition of thrust ratio of front wheels to rear wheels,which is an important parameter affecting the tractive performance of FWA tractor.
