Abstract: A shaft-hub connection system with angular play for bidirectional transmission of driving torque, comprising a shaft, a hub provided with a hole inside which the shaft is accommodated, and elements for connection which are interposed between the hub and said shaft. The connection elements comprise at least one functional assembly which comprises a slot in which a corresponding coupling element is accommodated so that it can move and is adapted to assume alternately a first position, in which it is retracted within the slot, a second position, in which it protrudes partially with respect to it along a first orientation, and a third position, in which it protrudes partially with respect to it along a second orientation, elastic compression elements interposed between the slot and the coupling element, a first seat and a second seat for the abutment of the coupling element.

Abstract: A torque limiting device, particularly for power transmission elements, is provided. The torque limiting device includes a first connecting member and a second connecting member, which is connected rotatably to a driven element. The first connecting member includes a motor driving disk and the second connecting member includes a sliding disk, and further includes a pin supporting body which comprises a drum that is assembled on the second connecting member and includes a plurality of radial holes, each one of which accommodates a pin that is pressed, toward the center of the drum, by elastic means, and abuts, with at least one of its faces which is inclined with respect to the central rotation axis of the second connecting member, against at least one corresponding abutment face.

Abstract: A gearbox is provided. The gearbox includes two mutually opposite walls and at least one shaft that supports at least one gear, the shaft passing through the gearbox from one of the two mutually opposite walls to the other. Each one of the ends of the shaft is coupled rotatably to a respective wall by a respective bearing. The gearbox also includes at least one rigid tension member, which is internal to the gearbox and acts between the two mutually opposite walls to perform their traction.

Abstract: A torque limiting device, particularly for power transmission elements, is provided. The torque limiting device includes a first connecting member and a second connecting member, which is connected rotatably to a driven element. The first connecting member includes a motor driving disk and the second connecting member includes a sliding disk, and further includes a pin supporting body which comprises a drum that is assembled on the second connecting member and includes a plurality of radial holes, each one of which accommodates a pin that is pressed, toward the center of the drum, by elastic means, and abuts, with at least one of its faces which is inclined with respect to the central rotation axis of the second connecting member, against at least one corresponding abutment face.