Abstract: A lampchanger preferably for use in a railroad signal lantern having a focusing lens which includes a horizontally rotatable turret adapted to support a plurality of lamps for indexing one of the lamps to the focal point of the lens. The turret includes a plurality of bayonet sockets for holding a lamp in which the sockets have resilient sides which taper inwardly away from the turret body for accurately securing the lamp in position. The turret includes a contact insulator having a radially extending slot adjacent each of the sockets with a power contact positioned in each of the slots. Each power contact includes a circular ridge for engaging the bottom of a lamp positioned in a socket for cleaning and making a good contact with the lamp. A power brush engages the rotatable turret and is positioned to engage the power contact and engages the slot of the insulator positioned in lamp operating position for mechanically holding the turret in position.

Abstract: A lampchanger for a light, such as a navigational light, having a rotatable turret for holding a plurality of lamps, fixed power contacts for engaging and lighting the lamp positioned in the operating position, and means for rotating the turret thereby placing a new lamp into operating position when a lamp burns out. The turret includes a body and a clamp yieldably urged against the body for releasably holding and locking the lamps between the clamp and the body. Lamps may slide into a tapered slot between the body and the spring-loaded clamp and are locked into place. Tilting the lamp towards the spring-loaded clamp releases the lamp. A stop limits the movement of the clamp on removing one lamp without releasing other lamps. The turret is of metal and has cooling fins for radiating heat energy. The electrical power contacts include a flat spring contact spiraling outward from the turret axis to pierce any oxides on the lamp contacts in advance of reaching the operating position.

Abstract: A position sensor for a rotatable lamp changer turret having a plurality of lamps which are rotated in sequence to an operating position as the lamps burn out. A circular cam is positioned on the turret that includes a first position indicating portion for each of the lamps for indicating when each of the lamps is in the operating position. The cam includes a second position indicating portion for indicating that all of the lamps have been rotated past the operating position. The second position indicating means is located for stopping the turret in a position with all the lamps out of the operating position for providing a visual alarm indication. A cam follower engages the cam and in turn actuates electrical switch means for controlling rotation of the turret. A third cam portion is positioned between each of the first cam portions for actuating the cam follower and the switch means for maintaining turret rotation until the first cam portions are engaged by the cam follower.