Abstract
The paper presents the newest construction of the hydraulic satellite pump/motor. In this study, the fracture of the hydraulic satellite motor working mechanism is investigated. Factors influencing the durability of satellite working mechanism have been described. The durability of the hydraulic satellite motor working mechanism at a load, corresponding to a pressure of 15 MPa supplied with refined rapeseed oil is very low. Analyses of construction and laboratory tests showed that the satellites teeth wear out the fastest. Results showed that bending fatigue and surface contact fatigue of the satellites are the main cause of the hydraulic satellite motor working mechanism failures.