Forced circulation electric heater

Claim 1

A forced circulation electric heater comprising, in combination: a housIng having opposed side wall surfaces, opposed front and back wall surfaces, a top surface, and a horizontal flat bottom surface; wheels mounted on said bottom surface for ease of transportation of said housing between locations of usage; an inlet port disposed in said front surface closely adjacent the bottom edge thereof; an outlet port disposed in said front surface at the top portion thereof; an airflow passageway disposed interiorly of said housing and interconnecting said inlet port and said outlet port; a first electric motor mounted in said passageway and having a motor shaft projecting horizontally outwardly therefrom in the direction of said outlet port and having a fan blade mounted on said shaft for rotation therewith in said passageway; a second electric motor separate from said first motor and identical to said first motor and mounted in said passageway adjacent said first motor, the second motor having its motor shaft disposed along a vertical axis normal to said shaft of said first motor and projecting vertically downwardly therefrom and having a fan blade mounted thereon for rotation therewith in said passageway; a pair of identical electrically energized heating coils electrically connected in parallel and mounted in spaced tandem relationship in said passageway downstream of said inlet port and upstream of said second motor and fan blade for heating the air flowing in said passageway from said inlet port to said outlet port; a U-shaped fuse block disposed in said passageway intermediate said heating coils and said second motor, the fuse block having a bight portion and upright leg portions terminating in a flat top surface, each flat top surface having a threaded aperture extending vertically thereinto; a terminal screw having a threaded shank adapted to be threadedly received in each associated aperture; a heat sensitive fuse link of a flat elongated rectangular configuration having apertures in opposite ends thereof adapted to be received beneath said terminal screws, said fuse link spanning said bight portion between said leg portions of said fuse block and rest on said flat top surfaces of said leg portions; and said fuse link being electrically connected in series with said heating coils and being selected to melt at a predetermined temperature within said passageway to break the electrical circuit between said terminal screws and de-energize said electrical heating coils to which said fuse link is electrically series connected; and means for selectively connecting the heating coils and first and second motors to a source of electric power.