Philips Infraphil 7525/72 heat lamp
bayonet mount (
bayonet socket
lamp base
The first Infraphil heat lamps from 1946 were made
of blown glass and the base of these lamps was
connected to the socket in the armature by means
of a so-called bayonet mount. Two electrical
contacts were located at the bottom of an isolator
that fitted into the metal base of the lamp. There
were three pins that sideways protruded the metal
base at an unequal mutual distance, causing the
base of the lamp to fit in the socket in one position
only. The pins fitted into three corresponding slots in
the socket. The lamp was gently pressed against a
spring-loaded construction in the socket and is than
hooked into it by a slight turn of the lamp. The early
"white" Infraphil heat lamps can easily be confused
with blended lamps that have been merchandised in
the same era and partly even in the same type of
armatures. Blended lamps however, are no heat
lamps but ultraviolet- or sunlamps.