Hydraulic motors or pumps currently available are of the type with radial or axial pistons and generally consist of a piston body, which acts on a rotatory eccentric shaft, which is inner in the case of the radial shape or rear in the case of the axial shape, whether the pistons of the piston body are straight or inclined. Said machines are adapted to convert the alternating motion of the pistons into the rotatory motion of the shaft with very high operating torques and pressure and can be used both as pumps and as motors in several activities of the construction industry. They all present the drawback that no equipment or apparatus of other associated machines is allowed to be arranged inside of them or pass through them. In these applications, generally on ordinary or planetary reduction gears, it is necessary to move the motor or pump to a position that is arranged on the side of the axis along which the torque is used, and to place it on a specially provided reduction gear, thus causing a consequent increase in the space needed and in manufacturing costs as well as a dispersion of power and, therefore, a decrease in mechanical efficiency. The object of the present invention is to provide a machine, in which the actuating pistons are arranged in a position that is tangential with respect to the rotation axis of the shaft that transmits the torque, thus allowing the creation of any kind of inner free space for the uses needed. Said pistons act on shafts that are arranged in a planet position with respect to the driving shaft and, in turn, transmit said torque by means of gearings, which can be of the ordinary or planetary type. The following description is relative to a motor with a number of 3 planets, but it also equally applies to a higher number of planet positions.