Grounded dual voltage trouble light and extension cord

Claim 1

A dual voltage trouble light and extension cord comprising a lamp holder (6) for a lamp bulb (2) having a high voltage A.C. filament (2a) and a low voltage D.C. filament (2b) a lamp guard (3) mounted on the lamp holder, a four conductor extension cored set (7) having a first plug (8) at one end and having the other end connected to said lamp holder (6), said first plug (8) having a first (8c) and second (8b) A.C. prongs, a ground pin (8a), and a female connector (8d), the prongs and ground pin being in grounded socket configuration, the first conductor (9a) of said cord set connected from said ground pin (8a) to a first terminal (3a) in said lamp holder connected to said lamp guard (3), the second conductor (9c) of said cord set connected from the first prong (8c) to a second terminal (2e) in said lamp holder connected to one end of said high voltage filament (2a), the third conductor (9d) of said cord set connected from said female connector (8d) to a third terminal (2d) in said lamp holder connected to one end of said low voltage filament (2b), the fourth conductor (9b) of said cord set connected from the second prong (8b) to a fourth terminal (2c) in said lamp holder connected to the other ends of said filaments (2a, 2b), a two pole switch in said lamp holder, one pole (4e) controlling the circuit in said second conductor (9c) to said second terminal (2e) and the other pole (4d) controlling the circuit in said third conductor (9d) to said third terminal (2d), a battery voltage socket (5) in said lamp holder having a ground contact (5a) connected to said first terminal (3a) and power contacts (5c, 5d) connected respectively to said third (2d) and fourth (2c) terminals, and an A.C. voltage socket (6) in said lamp holder having a ground contact (6a) connected to said first terminal (3a) and power contracts (6c, 6b) connected respectively to said second (2e) and fourth (2c) terminals.