Locking mechanism for an automobile seat

A locking mechanism has a lower member secured to a seat base, and an upper member that can rotate relative to the lower member and is secured to a seat back. A control element is capable of being rotated with a bar. A spring biases the control element toward a first configuration in which the control element drives a locking element radially away from the bar so that the locking element restricts rotation of the upper member relative to the lower member. The bar is capable of being rotated to a second configuration, and the control element rotates with the bar so that the locking element is capable of traveling radially toward the bar during the second configuration. A drive mechanism rotates with the bar and drives the locking element radially toward the bar during the second configuration, so that rotation of the upper member relative to the lower member is allowed. A transmission element is positioned between the control element and the bar. The transmission element has a first flange proximate the outer side of the upper member and a second flange proximate the outer side of the lower member, and the flanges restrict movement of the upper and lower members away from one another so that the transmission element functions as an axial safety device.