Abstract: A sand dosing and blocking device for sand spreading systems for vehicles, particularly rail vehicles with drive, has a sand supply container with an outlet opening which can be closed by a closing element for the dosed release of sand to a conveyor unit which is preferably pneumatically activated. The closing element is formed by a lifting rod of an electrically activated lifting magnet. The lifting magnet is arranged inside the sand supply container in the area of the outlet opening. Frequency control of the lifting magnet varies the dosed flow of sand, which may be varied in response to vehicle wheel speed.

Abstract: A mudguard gritter that can be easily installed on trucks, school buses, delivery trucks and semitrailers. It can be fixed to supports of existing mudguards. The mudguard gritter comprises a container forming a hopper having the shape of a conventional aileron, with a top rectangular opening of 150 mm per 600 mm and a bottom opening of 25 mm per 600 mm. The top site has a door with hinges that make it possible to fill up the container with fine gravel. A rake supports eccentric vertical stems, which meet through an intermediate guide, at the bottom, on a mobile plate driven by a dual action cylinder powered by compressed air passing through a valve whose control is on the dashboard of the vehicle.