Fluorescent lamp for use in explosive atmospheres such as mines

Abstract

Lamp having a lighting assembly, an inner guard assembly, and an outer guard assembly. The lighting assembly includes an elongated fluorescent bulb, starter and ballast members each having a socket portion removably connected to pins at the ends of the bulb, and an electrically conductive grounding bar interconnecting the starter and ballast members. The inner guard assembly includes a transparent cylindrical plastic housing enclosing the bulb, and end housings at the ends of the cylindrical housing enclosing the starter and ballast members respectively. The outer guard assembly includes an elongated support plate to which the end housings are fastened, a plurality of hoops fastened to the support plate at spaced intervals, and a plurality of guard rods parallel to the bulb housing welded across the hoops to provide a cage-like outer protection for the inner guard assembly. The ballast member is unitary, including one of the above-mentioned socket portions at one end removably electrically connected to the pins at one end of the bulb, and a plug at the opposite end removably electrically connected to a power outlet socket in the corresponding end housing of the inner guard assembly. The starter member is likewise unitary, including the other of the above-mentioned socket portions as an integral part thereof. The end housing at the starter member end of the lighting assembly has a removable cover for an opening through which the entire lighting assembly can be removed and replaced as a unit. The end housing at the ballast member end of the lighting assembly also has a removable cover providing access to the connection between the ballast member plug and the power outlet socket.