Study On 7.5-16 Tire Pressureand Pressure Acquisition Device

Tire-soil contact pressure affects the adhesion and trafficability of the vehicle and at the same time the soil compaction as well as the growth of crops. The smaller tires on the soil of average unit pressure is, the more uniform pressure distribution, the better the performance of the vehicle’s traction attached, the smaller soil compaction as well as the impact on crops. Therefore, the study on the pressure of tires to soil has a marked significance on theoretical and practical. Currently, most of the relevant experiment and pressure acquisition device is based on the hard ground test and design, the tire and soft ground and applied to the soft ground acquisition device research is few. In view of the above situation, research on pressure collecting device and ground pressure, the specific research content and conclusions are as follows:(1) Researches on tire-soil pressure acquisition device. Combined contact between tires and soil with pressure sensor method, the writer developed a tire-soil pressure acquisition equipment. 89C52 SCM-centered measuring device hardware system mainly consists of pressure signal detection module, AD conversion module, SCM control module and liquid crystal display module. The software system, including ADC0808 conversion module, LCD12864 LCD display module and system of the main program. The value of linear equation between the ground pressure and the liquid crystal display is determined after debugging and sensor calibration of measuring devices. Test shows, the design of pressure acquisition device is suitable for measuring the tire contact with the soil pressure. Compared with other devices, it is simpler to operate, has an extensive usage and more responsive.(2) Experiment on tire-soil pressure acquisition equipment. The contact pressure was tested of the 7.5-16 driving wheel of the tractor tires respectively in simulated tillage and stubble land. Due to the tractor tire contact with the soil, the contact shape and pressure distribution are very complex, so this paper only study of local earth pressure(a tread pattern and the corresponding groove). Instruments such as excel and origin are used to categorize and analyze the data.The results showed that in a hard ground, only the tread pattern grounded, so stress distribution is placed on the tyre pattern. In soft ground, tire pattern and grooves are grounded, so tread pattern and grooves have pressure, but still most of the pressure distribution are on the pattern. Under certain tire pressure, with the change of load, the tire ground pressure on the central pattern changes little, and are relatively stable. Tires interaction between different decorative patterns affects ground impact stress size and distribution. The grounding shape of tires concave and convex trait, which is formed together between floor, tire pressure, load and work together. With the loss of the tire pressure, tire pattern have been ground pressure is reduced, and more and more evenly distributed. The best way to change the earth pressure distribution is to change the tire pressure, and the second is to change load. Using regression method to analyze tread pattern average ground pressure, the regression equation is established between average contact pressure with the tire pressure and load. The use of this equation can predict the tread pattern of evaluation of ground pressure.