Hydraulic motor with stationary axle and rotating fluid distributor

A hydraulic motor, comprising:

• a surrounding rotatable frame casing;
• a stationary internal cylinder block with radially arranged cylinders and a stationary axle of the hydraulic motor attached thereto;
• pistons reciprocating in the cylinders and bearing the inner surface of the frame casing, said inner surface being formed as a running surface guiding the movement of the pistons;
• feed and exhaust channels for the hydraulic fluid;
• a fluid distributor mounted around the axle to rotate together with the frame casing, for the distribution of the hydraulic fluid from said feed channel in the stationary axle into cylinder chambers and away therefrom to said exhaust channel in the stationary axle via openings provided in the cylinder block;
• at least two ring-shaped spaces provided between the rotatable fluid distributor and the stationary axle thereby forming a rotatable interface between the stationary axle and the fluid distributor, said spaces being formed in the feed and exhaust channels for the hydraulic fluid, said ring-shaped spaces being formed by stepwise formations in counter surfaces of the fluid distributor and the axle, a first ring-shaped space being formed between a first stepped surface of the fluid distributor and a first stepped counter surface of the axle, a second ring-shaped space being formed between a second stepped surface of the fluid distributor and a second stepped counter surface of the axle;
• and
• the area of the end counter surface facing the cylinder block in the ring-shaped spaces being so dimensioned that the force caused by the hydraulic fluid in the ring-shaped spaces presses the fluid distributor against the cylinder block compensating for the force separating the fluid distributor and the cylinder block.