Warning lamp

A warning lamp has a reflector (44) mounted on a rotary platform (20) which is journalled on a hollow pillar (18) and driven by an electric motor (70). A light source (42) is mounted on the pillar (18) and has a centre contact (48) engaging with a connector (52) within said pillar (18). The electric motor (70) is arranged to drive a pulley (78) formed from resiliently compressible material and comprising a plurality of peripheral ribs (80-86) having annular recesses therebetween. The ribs (80-86) engage with the rotary platform (20).