Tire safety support and rim and support assembly containing centering means and with facilitated mounting

A wheel assembly comprising a rim and a pneumatic vehicle tire safety support, said support being designed to be installed inside a tire by a relative translation operation around a bearing of said rim, having an axially front face and an axially back face and comprising a base intended to fit around said bearing as well as a body connected to said base, said bearing having an engagement edge and said translation operation comprising moving the engagement edge of the rim bearing from said axially front face of the support to said axially back face, wherein said assembly comprises a plurality of circumferentially distributed protuberances said protuberances being arranged on a portion of said rim bearing and having a radial dimension greater than a radial dimension of a remainder of said rim bearing disposed beneath said support in a radially inward direction, in order to create a mechanical tightening between said support and said bearing and to provide centering of said support on said bearing, wherein said base of said safety support comprises a reinforcing structure and said reinforcing structure has stiffness in response to extension forces and weak bending strength, so as to have a substantially polygonal shape over said protuberances.