Belt retractor with an integrated belt pretensioner and an energy converter

A belt retractor comprising a frame with a locking toothing, a belt reel rotatably mounted in said frame, a rotary pretensioning drive associated with said belt reel, a torsion bar mounted coaxially in said reel, the torsion bar having a first end connected to the belt reel and a second end connected to a coupling disc, an internally toothed ring surrounding said coupling disc and fixed with the frame, at least one locking pawl pivotally mounted on a face of said belt reel for selective engagement in said locking toothing, and a control disc is mounted for limited rotation on said second end of the torsion bar, and said control disc engaging said locking pawl at least during a phase of energy conversion, thus preventing it from engaging with said locking toothing, said phase of energy conversion following forced rotation of said belt reel by said rotary pretensioning drive and being achieved by twisting of said torsion bar while said second torsion bar end is blocked with respect to said frame by means for blocking on said coupling disc.