Device for aligning in a row and straightening preforms, the device being intended to be applied to axisymmetric preforms that have a neck separated from a body by an annular support face that protrudes with respect to the body, the device comprising a centrifuge bowl formed by: - a horizontal circular turntable turning about a vertical axis; - a fixed peripheral guard-bar; - at least a first angular sector for aligning the preforms against the guard-bar; - at least a second angular sector for straightening the preforms, which is arranged downstream of said first angular sector and along which the bowl has a peripheral gap in order to allow aligned preforms, which are supported by their support face, to be straightened, the body hanging outside of the bowl through said gap while the neck remains inside the bowl; - at least one outlet passage arranged downstream of said straightening angular sector in the direction of rotation of the turntable; the device comprising means for ejecting incorrectly aligned preforms from the row of correctly aligned and straightened preforms; wherein: in this alignment sector, the guard-bar extends vertically above the turntable such that the outer edge of the turntable is arranged outside of the centrifuge bowl; at least along the entire straightening second sector, the guard-bar has a rail for supporting the support face; the rail protrudes radially inwards at the same level as the upper face of the turntable in order to outwardly delimit the gap, the rail extending as far as the outlet passage; the device comprises an outlet conveyor for the aligned and straightened preforms; the conveyor is tangentially connected to the turntable in continuity with the outlet passage for the correctly aligned and straightened preforms; characterized in that: said means for ejecting incorrectly aligned preforms are active ejection means comprising a wheel (40, 42) with paddles that is arranged so as to turn, within the centrifuge bowl above the turntable, about a fixed axis (C, E), the space through which the paddles sweep excluding the passage of the necks of the correctly aligned preforms; the primary sorting wheel is arranged downstream of the straightening angular sector; the conveyor comprises a horizontal slide formed of an outer rail that extends the rail of the guard-bar and of a parallel inner rail that tangentially extends the outer edge of the turntable, the outer rail and the inner rail being spaced apart in such a manner as to support a straightened preform by its support face. - a horizontal circular turntable turning about a vertical axis; - a fixed peripheral guard-bar; - at least a first angular sector for aligning the preforms against the guard-bar; - at least a second angular sector for straightening the preforms, which is arranged downstream of said first angular sector and along which the bowl has a peripheral gap in order to allow aligned preforms, which are supported by their support face, to be straightened, the body hanging outside of the bowl through said gap while the neck remains inside the bowl; - at least one outlet passage arranged downstream of said straightening angular sector in the direction of rotation of the turntable; in this alignment sector, the guard-bar extends vertically above the turntable such that the outer edge of the turntable is arranged outside of the centrifuge bowl; at least along the entire straightening second sector, the guard-bar has a rail for supporting the support face; the rail protrudes radially inwards at the same level as the upper face of the turntable in order to outwardly delimit the gap, the rail extending as far as the outlet passage; the device comprises an outlet conveyor for the aligned and straightened preforms; the conveyor is tangentially connected to the turntable in continuity with the outlet passage for the correctly aligned and straightened preforms; characterized in that: said means for ejecting incorrectly aligned preforms are active ejection means comprising a wheel (40, 42) with paddles that is arranged so as to turn, within the centrifuge bowl above the turntable, about a fixed axis (C, E), the space through which the paddles sweep excluding the passage of the necks of the correctly aligned preforms; the primary sorting wheel is arranged downstream of the straightening angular sector; the conveyor comprises a horizontal slide formed of an outer rail that extends the rail of the guard-bar and of a parallel inner rail that tangentially extends the outer edge of the turntable, the outer rail and the inner rail being spaced apart in such a manner as to support a straightened preform by its support face.