BACKGROUND: Currently used in various sectors of the national economy, numerous wheeled suspensionless vehicles on pneumatic tires have a low level of vibration protection of the frame and limited cross-country ability. Therefore, the development and study of the design characteristics of a pneumatic wheel with increased elastic-damping properties and cross-country ability is a relevant technical problem. AIM: Development of the design and study the vibration-protective properties of a pneumatic wheel with an external spring-hydraulic mini-suspension to improve the ride smoothness and cross-country ability of large-sized suspensionless vehicles. METHODS: A description of the design of a wheel with mini-suspension and a support roller is presented. The wheel modeling was carried out in the PascalABC software, which takes into account the nonlinearity of the total force of the pneumatic tire and the spring-hydraulic mini-suspension, which is installed parallel to the tire at an angle to the vertical axis of the wheel. The test method consisted of comparison of free and forced vibrations of the rear pneumatic wheel of the MTZ-82 BELARUS tractor with a 400-965/15.5-38 tire, which operated without and with mini-suspension at a vertical load of 0.6 tons and various excessive pressure in the tire. RESULTS: The results of computational and experimental studies show that if the tire is radially compressed by 75 mm, the excess pressure inside the pneumatic wheel almost does not change, and if the pressure in the tire decreases from 1.6 to 0.4 bar, the resonant vibration frequency of the standard wheel axle decreases by 25%, while the dynamic coefficient remains unacceptably high (more than 5), leading to the tire breakaway from the supporting surface. Installing a mini-suspension parallel to the wheel in the form of a spring-hydraulic shock-absorbing strut leads to an increase in the resonant frequency by 1 Hz, however, the resonant peaks are reduced by almost 3 times to a dynamic coefficient of 2.5...2, which significantly increases the ride smoothness of suspensionless vehicles and reduces the likelihood of wheel breakaway from the supporting surface. CONCLUSION: It was found with the studies that the proposed wheel with a mini-suspension as a spring-hydraulic strut and a support roller has a relatively simple design, ensures high vibration-protective properties with small amplitudes of kinematic disturbance and can be used to improve the ride smoothness and cross-country ability of wheeled suspensionless vehicles.
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