The invention relates to a valve assembly (50) of a radial piston hydraulic apparatus (1). Said apparatus includes a cylinder block (4) insertable onto a shaft (2) by translation. Said assembly (50) includes: a valve (51) in contact with said cylinder block (4); a valve train cover (52); and a first (541) and second (542) chamber that are defined, respectively, by a first (511, 521) and second (512, 522) space that are located at the interface between said valve (51) and said valve train cover (52), and are intended for the pressurized fluids that enable the conversion of pressure and/or mechanical stress. Said assembly (50) includes an additional section (54) defined by a third space (541, 542) located at the interface between said valve (51) and said valve train cover (52). Said section (54) is intended for receiving a pressurized fluid such as to enable the cylinder block (4) to be inserted onto the shaft (2).

An axial piston machine has a displacement volume that is adjustable by a double-acting control cylinder, which is connected to an auxiliary pump via a fluid flow path that includes a first, a second, and a third control assembly. The transfer point is the point of the fluid flow path at which the plate-like housing part contacts the pot-like housing part. The receiving bore of the first, second, and third control assemblies are each arranged directly in the pot-like housing part. The part of the fluid flow path which is arranged downstream of the transfer point extends over its entire length directly in the pot-like housing part.

A method is for operating an axial piston machine whose displacement volume is continuously adjustable using a double-acting control cylinder having two oppositely acting control chambers. The method includes providing a corresponding axial piston machine. An electrically adjustable pressure control valve is connected to one control chamber. Another control chamber is connected to an electrically adjustable 3/2-way switching valve. The method includes providing a target control pressure difference. A zero case is defined as a case in which the target control pressure difference is essentially zero. A positive case is defined as a case in which the target control pressure difference is positive. A negative case is defined as a case in which the target control pressure difference is negative. The method further includes calculating a first and a second control pressure. A case differentiation includes determining whether the zero case, the positive case, or the negative case is present.