Matsushita Electric Works, Ltd.

Nobuichi Fujishima

Kuniharu Ichikawa

Hideharu Nakano

Shuhei Ochi

A portable electric hair dryer includes an electric heater and blower forming a load circuit energized from a pair of power feeder lines connected to a source of AC power. A zero phase-sequence current transformer is electrically coupled to the power feed lines between the connection thereof to the power source and the load circuit to serve as a current leakage detector. An electricaly conductive heater enclosure disposed within the housing of the hair dryer receives the heater and is electrically isolated from the power feed line serving as the hot line. The heater enclosure is electrically connected to the power feeder line serving as the neutral line by a ground wire extending between the heater enclosure and the point at which the zero phase-sequencing transformer is coupled to the power feeder lines to define a leakage current path between the hot line and the heater enclosure should the hair dryer be dropped in water. Upon detection of leakage current the detector operates a manually resettable switch associated with the power feeder lines to disconnect the load circuit from the AC power source, thus eliminating the danger of electrical shock and ensuring safe retrieval of the hair dryer from the water. The leakage detector and switch may be incorporated into a plug provided on the connecting end of the power feeder lines or they may be incorporated into a wall mounted holder for the hair dryer.

Portable electric hair dryer with electric shock protection circuit

A foldable hair dryer of the hand-held type which includes a housing incorporating an electrically operated means for producing a flow of heated air, a hand grip pivotally attached to the housing, and a power cord extending from the housing. The hand grip is rotatable to a operational position where it extends outwardly from the housing, and to a folded position where it is folded on a part of periphery of the housing. Formed along the periphery of the housing is a first groove which cooperates, when the hand grip is in the folded position, with the second groove formed in the hand grip to define a peripheral channel extending across the housing and the folded hand grip. The power cord can be received in the peripheral channel thus formed and be wound up along the entire periphery of the hair dryer when the hand grip is brought in the folded position. The hand grip is shaped to have a cap portion which closes an air discharge outlet when it is in the folded position so as to prohibit the entry of foreign matter therethrough. Means incorporated in the hair dryer for producing a flow of heated air is energized by the operation of a knob which is accessible from the exterior of the housing and is locked in position not to energize the means for producing a flow of heated air until the hand grip is brought in the operational position, thus preventing an accidental flow of heated air blown from the outlet when the hand grip is in the folded position, since such accidental flow would otherwise damage the hand grip and the power cord wound thereon.

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Hikone, Japan

Nobuichi Fujishima