Hydraulic block for a hydraulic power unit of a hydraulic vehicle braking system

A hydraulic block arrangement for a hydraulic power unit of a hydraulic vehicle braking system, the hydraulic block arrangement comprising:

• a hydraulic block having a power cylinder borehole in which a power piston is axially displaceable;
• and
• a guide bushing that is situated in the power cylinder borehole in a manner by which the power piston is radially guidable in the power cylinder borehole;
• wherein:
• the guide bushing includes a circumferential sealing groove in its inner circumferential surface, in which a first piston seal is situated, which provides sealing between the power piston and the guide bushing;
• a circumferential groove, which is scored into an exterior surface of the guide bushing, extends in a circumferential direction over a circumferential region of the guide bushing;
• a first plurality of brake fluid lines extend to the circumferential groove;
• each of the first plurality of brake fluid lines opens into the circumferential groove at a respective circumferential coordinate of the circumferential region;
• the respective circumferential coordinates differ from one another;
• and
• the circumferential groove thereby provides a hydraulic communication between the first plurality of brake lines on the outside of the guide bushing.