Studying the operation of the pneumohydraulic shock absorber with zero bottoming in the suspension of a transport and handling machine

Introduction: The movement smoothness of transport and handling machines (THM) (excavators, cranes, road maintenance equipment, etc.) on a vehicle chassis significantly affects their durability as a result of the large weight of equipment and uneven load distribution along the axes of the base chassis, which causes heavy dynamic loads when moving along roads with imperfect pavement. However, THM often have to move along those very roads. Purpose of the study: We aimed to increase the movement smoothness of THM on a vehicle chassis by using a shock absorber of new design as the main vehicle undercarriage suspension element. Methods: The hydropneumatic shock absorber is considered the most common. The principle of its operation is based on hydraulic resistance that occurs when the piston with the rod move in a space filled with oil, while the gas in the closed part is compacted, compensating for changes in the internal volume. Most often, the main disadvantage related to the operation of hydropneumatic shock absorbers (HPSA) is the probability of bottoming when hitting a barrier (obstacle), which results in dynamic loads reducing the service life of the vehicle and the parts of the shock absorber. Results: The paper describes a new shock absorber design ruling out bottoming, provides a mathematical model of its elastic response, and presents the results of modeling in Mathcad, confirming the operability of the device.