Lamp and lampholder with peripheral locking means

An assembly of

• a lamp comprising
• a lamp bulb and
• a lamp base, which lamp base comprises
• a projection located in a substantially central position of the lamp base and extending in a direction away from the lamp bulb,
• at least one lock-engaging portion, and a substantially flat base surface opposed to the lamp bulb and surrounding the projection, the at least one lock-engaging portion beomg located on the edge of the base surface surrounding the projection remote from the central projection;
• and
• a lampholder for cooperation with a lamp, the lampholder comprising
• an aperture in a substantially central position of the lampholder,
• at least one counter lock-engaging portion, and
• a substantially flat holder surface surrounding the aperture, the at least one counter lock-engaging portion being located on the edge of the holder surface surrounding the aperture remote from the central apertureas
• wherein
• the projection of the lamp is smaller than the aperture of the lampholder for cooperation of lamp and lampholder, and
• the at least one lock-engaging portion is located on the edge of the base surface for cooperation with at least one counter lock-engaging portion located on the edge of the holder surface.

A lamp comprising

• a lamp bulb;
• and
• a lamp base comprising
• a substantially flat base surface opposed to the lamp bulb;
• a central projection, located in a substantially central position of the lamp base and extending from the base surface in a direction away from the lamp bulb;
• at least one lock-engaging portion located on the edge of the base surface remote from the central projection,
• key means, comprising at least one aperture in the central projection, the key means serving to identify the lamp;
• a plurality of contact members, projecting from the base surface opposite the lamp bulb, and distributed so that at least two are opposite one another about the central projection.

A lamp holder comprising

• a substantially flat holder surface for receiving a base surface of a lamp;
• an aperture in a substantially central position of the holder surface;
• at least one counter lock-engaging mechanism located on the edge of the holder surface remote from the aperture for receiving at least one corresponding lock-engaging mechanism on the lamp;
• counter key means for receiving a key means on the lamp and comprising at least one projection in the aperture, the key means serving to identify the lamp;
• and
• a plurality of counter contact members below the holder surface, for receiving a plurality of corresponding contact members on the lamp, and distributed so that at least two are opposite one another about the central projection.