Pressure relief valve assembly, modular pressure relief valve assembly, and hydraulic control assembly having such a pressure relief valve assembly

A modular pressure relief valve assembly for selectively configuring a constant spring bias or a variable spring bias pressure relief valve having a constant spring biasing or a variable spring biasing, comprising:

• a pressure relief valve comprising:
• a valve body biased against a valve seat by a spring, the valve body guided in one of a valve bushing and a further valve bushing, the valve body including a first control surface subjected, in an opening direction, to a pressure to be limited, and a second control surface subjected to a control pressure in the opening direction,
• the valve bushing configured to be axially moved in a valve bore of a housing bore to adjust the variable spring biasing;
• and
• the further valve bushing has an external threading integral with said further valve bushing, the external threading being designed for screwing into the housing bore,
• wherein an axial support of the one of the valve bushing and the further valve bushing in the housing bore is provided by a fixing device disposed on the valve bushing,
• wherein the one of the valve bushing and the further valve bushing has a radially protruding sealing collar which sealingly sits against a peripheral wall of the housing bore and which seals an annular chamber carrying the pressure to be limited against an annular control chamber carrying the control pressure, and
• wherein both the annular chamber and the annular control chamber are delimited in a radial direction, at least in sections, on one side by the housing bore and on another side by the valve body.

A hydraulic control assembly comprising:

• an axial piston machine guided in a closed circuit;
• and
• a pressure relief valve assembly comprising:
• a pressure relief valve comprising:
• a valve bushing received in a valve bore of a housing bore;
• a valve body biased against a valve seat by a spring, the valve body guided in said valve bushing, the valve body including a first control surface subjected, in an opening direction, to a pressure to be limited, and a second control surface subjected to a control pressure in the opening direction,
• wherein an axial support of the valve bushing in the housing bore is provided by a fixing device disposed on the valve bushing,
• wherein the valve bushing has a radially protruding sealing collar which sealingly sits against a peripheral wall of the housing bore and which seals an annular chamber carrying the pressure to be limited against an annular control chamber carrying the control pressure,
• wherein both the annular chamber and the annular control chamber are delimited in a radial direction, at least in sections, on one side by the housing bore and on another side by the valve body, and
• wherein the pressure relief valve assembly is configured to set a feed pressure of the axial piston machine.