Дослідження стійкості роботи гідроприводу, чутливого до навантаження, на базі мультирежимного гідророзподільника

Abstract

The article describes a new scheme of a hydraulic drive, which, thanks to the original design of a multimode directional control valve, has energy-efficient properties that are characteristic of load-sensing hydraulic drives. The proposed design of the multimode directional control valve ensures the operation of the hydraulic drive in four modes – unloading the hydraulic pump, regulating the flow of the hydraulic motor, the maximum flow of the hydraulic motor and protection against overload. In each of these modes, the hydraulic drive operates with low power losses due to the presence of a constant balancing pressure drop. This value is formed by a combination of design parameters of the directional control valve. The proposed value of the value of the balancing pressure drop of 0,7-0,8 MPa provides high energy efficiency of the hydraulic drive in the most critical operating mode – regulation of the hydraulic motor flow. In order to ensure the stability of the energy-efficient operation of the hydraulic drive in this mode, a research was made of the stability of transient processes with various combinations of design parameters of the overflow valve of the hydraulic control valve, as well as changes in the operating conditions of the hydraulic drive. As a result of theoretical researches, on the basis of mathematical modeling of working processes, combinations of design parameters of the hydraulic lock and the spool of the overflow valve were identified, which ensure the stability of the hydraulic drive in the mode of regulating the flow of the hydraulic motor. In particular, these are such parameters as the stiffness of the springs of the hydraulic lock and the overflow valve, the diameter and angle of inclination of the edge of the overflow valve spool, the area of the radial holes and the auxiliary choke of the overflow valve. It was also determined that in this mode, the stability of the hydraulic drive will be ensured under conditions of a load pressure of up to 20 MPa, a hydraulic motor flow rate of 100 l / min and a working fluid temperature of 80 °C.