The high pressure axial piston pump: This variable type pump, the output pressure is less than a constant pressure setting of the output pressure of the full displacement, oil, i.e. quantitative output, the output fluid pressure reaches the set pressure, it automatically adjusting The pump flow to maintain the Hengli pressure, to meet the requirements of the system. Pump output constant value, according to need, within the regulating range can be steplessly adjusted. The structure shown in Figure 5, the structure of the pump output pressure oil through oil inlet to the of variable piston lower chamber and the constant pressure valve control at the same time, when the output pressure is less than the setting of constant pressure, constant pressure on the spool hydraulic thrust is less than the set spring force of the constant pressure valve is turned on, the pressure oil to enter the variable piston pressure in the lowest position, the pump output pressure of the full displacement oil: when the pump in the set pressure work, the role of the constant pressure on the spool thrust is equal to the set spring force, the constant pressure valve inlet port at the same time in the open state, so that the upper and lower chambers of variable piston hydraulic thrust equal variable piston balance in a position to increase the hydraulic damping (load), hydraulic elevated instantaneous, constant pressure valve exhaust ports open large oil inlet off a small, variable piston chamber cavity pressure decreased, variable piston moves up, the pump flow rate decreases until the pressure drops below the set constant pressure, which work when variable piston in the new equilibrium position. Sales Miss Mo: 13927792326 Conversely, if hydraulic damping (load) is reduced, hydraulic instantaneous decline, constant pressure valve inlet port open drain port off small, variable increases, until the pressure rises to the set constant pressure.