SCHALENRAD

A split wheel assembly for reception of pneumatic tires is provided with a safety feature to ensure that the two halves of the wheel cannot be dismantled when the tire thereon is pressurized. The assembly flanges of the two wheel portions have series of assembling apertures which register in pairs. The aperture on one of the flanges is circumferentially extending, and has a narrow end and a broad end. The narrow end of the aperture extends to an axially extending depression on the surface presented towards the flange of the other rim section. A bolt passes through the apertures, for assembling purposes, the bolt having a washer which fits into the depression, and having a securing nut which is sized so as to pass through the broad end of the aperture but not through the narrow end. In order to dismantle the wheel, the nut must be loosened sufficiently to cause separation of the two rim flanges so that the washer can move out of the depression, and the bolt can be moved axially to the broad end of the aperture. Such separation of the rim sections automatically causes deflation of the tire, if it is pressurized.