Drive shaft with lubricated accident-prevention end protections

A drive shaft comprising:

• an outer hollow shaft comprising a first end and a second end;
• an inner shaft inserted slidable into the outer shaft and comprising a first end and a second end, wherein the outer shaft and the inner shaft are torsionally coupled and form a telescopic shaft;
• a first universal joint with a first inner fork connected, by means of a respective sleeve, to the first end of the inner shaft;
• a second universal joint with a second inner fork connected, by means of a respective sleeve, to the first end of the outer tubular shaft;
• an accident-preventing protection comprising:
• a telescopic tubular protection surrounding the outer shaft and the inner shaft and comprising a first protection tube and a second protection tube, one of which is inserted slidable into the other, and sliding with respect to each other;
• and an end protection for each of said first universal joint and second universal joint, each end protection being constrained to the telescopic tubular protection, each end protection comprising a rigid annular structure, through which the end protection is constrained to the inner fork of the respective universal joint, the rigid annular structure comprising an annular sliding block slidably engaged in an annular groove of the sleeve of the inner fork of the respective universal joint, the sleeve of the inner fork comprising an annular bearing track for the end protection, the annular bearing track and the annular groove being offset with respect to each other in the direction of the axis of the drive shaft, wherein the annular structure of the end protection comprises:
• a sliding ring forming a sliding surface into sliding contact with the annular bearing track;
• and a containment sleeve for containing the sliding ring and the annular sliding block, wherein the containment sleeve is torsionally and axially constrained to the sliding ring.