Electric heating unit

Claim 2

An electric heating unit comprising, a casing containing heating elements, a housing for the casing, the housing including front and back panels disposed respectively over and spaced from the front and rear surfaces of the casing, said panels defining air channels between them and the surface of the casing, the panels being spaced apart at their top and bottom, the upper and lower ends of the casing being spaced from the adjacent ends of the panels, the spacing between the panels at their upper and lower ends being constricted to provide air inlet and outlet openings of approximately the width of the air channels, the front panel having vertical edges provided with rearwardly bent rim portions, the rim portions being provided at their rear edges with inwardly directed flanges, said flanges having slits, the vertical edges of the rear panel and the heater casing being provided with a forwardly bent rim, the rims on the rear panel and casing being in juxtaposed contact with each other, the juxtaposed rims being provided with forwardly projecting hookshaped securing members and the securing members being received in slits in the flanges of the front plate to lock the front plate, rear plate and the casing together.

Claim 3

An electric heating unit according to claim 1, wherein the front panel is provided at its top with a hollow, triangular box that aids in the constriction of the air outlet opening, said box having a lower angular deflecting surface.

Claim 4

An electric heating unit comprising, a closed casing containing and enclosing heating elements, said casing being closed at the top and bottom and including overlapped flanges at said top and bottom, the heating elements being spaced from inner wall surfaces of the casing whereby air spacing is provided between the heating elements and the inner wall surfaces of the casing, a housing fitted around the casing and spaced therefrom to provide air spaces between the exterior surfaces of the casing and the inner wall surfaces of the housing, said housing including front and rear panels provided with juxtaposed side members disposed over and spaced from parts of the casing to thereby provide air spacing between said panels and parts of the casing, the panels being arranged to provide air inlet and outlet openings between them, the inlet opening being located at the bottom of the housing below the casing and the air outlet being located at the top of the housing above the casing, at least one of the panels having hook-shaped locking members at its ends of its side members which enter slits at the ends of the side members of its companion panel to thereby hold the panels together, the spacing of the housing from the casing causing parts of the housing to be heated by convection from the heating elements and at a lower temperature than that of the heating elements.

Claim 5

An electric heating unit comprising, a closed casing containing and enclosing heating elements, said casing being closed at the top and bottom and including overlapped flanges at said top and bottom, the heating elements being spaced from inner wall surfaces of the casing whereby air spacing is provided between the heating elements and the inner wall surfaces of the casing, a housing fitted around the casing and spaced therefrom to provide air spaces between the exterior surfaces of the casing and the inner wall surfaces of the housing, said housing including front and rear panels provided with juxtaposed side members disposed over and spaced from parts of the casing to thereby provide air spacing between said panels and parts of the casing, the panels being arranged to provide air inlet and outlet openings between them, the inlet opening being located at the bottom of the housing below the casing and the air outlet being located at the top of the housing above the casing, at least one of the panels having hook-shaped locking members at its ends of its side members which enter slits at the ends of the side members of its companion panel to thereby hold the panels together, the spacing of the housing from the casing causing parts of the housing to be heated by convection from the heating elements and at a lower temperature than that of the heating elements.