Electric hairdryer having a cage-shaped heater element

Claim 1

An electric hair dryer comprising an elongated casing of circular cross section having a rear end perforated by air inlet ports and a front end perforated by air outlet ports, said casing containing: an electric motor having a rearwardly extending shaft, a motor cradle supporting said motor, an axial fan impeller on the shaft of said motor, an electric heater element in the shape of at least one hollow cylindrical open-ended cage comprising a plurality of parallel, spaced-apart, electrically heatable metal strips connected in series at alternate ends by bridging portions, said strips being inclined to the ideal circumference of said at least one cage, so as to form air guide vanes; said at least one cage having its ends facing the front and rear ends, respectively, of said casing, and being mounted on end rings of a non-conductive material; and electric switching and controlling means carried by said casing and operatively connected to the at least one heater element and to said motor for controlling energization thereof; the hair dryer being characterized by the front portion of said casing tapering towards its front end; that said electric motor is of smaller diameter than said cage and partly extends into the inner space of said cage; that said impeller is mounted on the rearwardly extending shaft of said motor upstream of said cage; that said at least one cylindrical cage is positioned said casing in coaxial alignment therewith and between said casing and said motor thereby creating an outer annular space between said casing interior and said at least one cage having a cross section gradually decreasing towards the front of said casing where it is closed by contact of said front end ring with the inside of said casing, thus forming a duct for conveying a portion of the air delivered by said impeller through said heated air guide vanes of said at least one cage into said at least one cage interior, and forming an inner space between said at least one cage and said motor for conveying the remaining air volume direct into said at lease one cage interior, while cooling said motor surface; and that said motor is located inside said at least one cage in a manner creating a space downstream of said motor for mixing the air volume heated by passage through said heated strips of said at least one cage with the cooler air volume conveyed through said inner space.