Abstract: A chain-carrying pulley (1) is journalled on a shaft (3) fastened to an arm (4) pivotally connected to another arm (5) which in turn is rigidly fastened to the rear axle casing (6) of a vehicle. An inflatable bellows (7) extends between the arms. When inflated, for instance by pressurized air, the bellows displaces the movable arm (4) from a folded position relative to arm (5) bringing the pulley (1) into contact with the wheel. The pulley is returned to a storage position by springs (10) joined to the arms when the bellows is deflated.

Abstract: Anti-skid device especially for motor vehicle comprising elastic arms (2) assembled to a disc unit. In use the disc unit is brought close to the vehicle wheel, the friction of which is to be increased, and the outer ends (3) of the arms are successively drawn in between wheel and ground to increase the friction. Apart from their friction increasing portion (3) the arms (2) are extremely elastic and extend practically to the centre of rotation and bearing of the disc. Above the arms there is arranged a disc (5) extending out to the vicinity of the transition of the arms (2) into the friction increasing members (3). Moreover, beneath the arms a ring (6) is arranged which is attached between the arms (2) to the points (7) of attachment of the disc. In this way the disc is given a plane appearance ensuring that the friction increasing members (3) of the arms can obtain defined feed-in positions relative to the vehicle wheel.