High pressure pump with improved hub

A high-pressure pump for pumping a first liquid, known as the transferred liquid, of the type comprising a main unit (18) for pumping the transferred liquid, which unit is actuated by a secondary unit (20) for pumping a second liquid, known as the working liquid, the secondary unit (20) comprising a hub (64) mounted so as to rotate in a housing (16) forming a bearing, and at least one piston (54) for compressing the working liquid, which can move approximately parallel to the axis (X) of rotation of the hub, returned elastically against a swashplate (62) for actuating this piston (54), carried by the hub, characterized in that the hub (64) comprises a peripheral cylindrical surface (SG) for guiding the rotation in the housing (16), extended by a shoulder (FE) for axially positioning the hub in the housing (16), the peripheral guide surface (SG) and the axial positioning shoulder (FE) cooperating respectively with complementary rotational guiding means (SP;

• 124) and complementary axial positioning means (FP;
• 126) carried by the housing (16), the axial positioning shoulder (FE) being urged against the complementary axial positioning means (FP;
• 126) carried by the housing (16) and by the elastic return force of the piston (54) and the pressure of the working liquid in contact with the swashplate (62).