Device for fixing and adjusting the optical block of a lamp on a motor vehicle

A device for fixing and adjusting an optical block on a motor vehicle, said optical block being of the type including a plurality of peripheral positioning tabs, said device comprising a one-piece support suitably shaped to co-operate with the peripheral edge of said optical block, said support being provided firstly with a plurality of mounting members enabling said support to be adjustably fixed to a vehicle, and secondly with a plurality of clamping members suitable for co-operating with said positioning tabs on said optical block in order to position said support and to hold said support relative to said optical block, each of said clamping members having a tongue hinged about a hinge on an outwardly-directed radially-extending fixed portion of said one-piece support and constituting an extension thereof, and each of said clamping members further including an orifice suitable for imprisoning a corresponding one of said positioning tabs during a clamping operation performed by rotating said clamping member through 180.degree. about said hinge, and fastening means for resiliently fixing said clamping members to said fixed radially extending portion of said one-piece support, the relative positions of said mounting members and said clamping members ensuring that said optical block is correctly positioned on said vehicle.