Electric Hair Drying Device

Abstract

An electric hair dryer includes an elongated cylindrical casing having an air inlet at one end and another air inlet intermediate the two ends of the casing. An axial flow fan is located adjacent each inlet, with the fans being of opposite hand so as to produce opposed air flows within the casing. An air outlet is provided in the peripheral wall of the casing between the fans and an electric heating unit is provided in the casing between the fans and the outlet whereby air is drawn into the casing by the fans through the inlets, heated and ejected through the outlet. The casing may be in the form of two semi-cylindrical shells joined along their longitudinal edges. The axial flow fans and an electric driving motor therefor are carried by one of the shells independently of the other shell. The electric heating unit includes a frame assembly having a disc with a diameter equal to the inner diameter of the casing to separate the air flow of the first impeller from the air flow of the second impeller.

Description

This invention relates to blower devices, for example hair dryers.

According to the present invention there is provided in a blower device, an elongate hollow casing, a first fan impeller located adjacent one end of the casing, a second fan impeller spaced axially of the casing from the first fan impeller, the first and second impellers being arranged to produce opposed air flows within the casing, and drive means for the impellers, said casing having an outlet for the air flows produced by said fan impellers.

Further according to the present invention there is provided a hair dryer comprising an elongate hollow cylindrical casing including a first substantially semi-cylindrical shell and a second substantially semi-cylindrical shell, said casing defining a first air inlet at one end and a second air inlet intermediate the length of the casing, and an air outlet in the wall of one said shell intermediate the two inlets, a motor mounted in the other said shell at a location between the second inlet and that end of the casing remote from the first inlet, a first, axial flow, fan impeller mounted adjacent the first inlet, said impeller including blades of one hand, a second, axial flow, fan impeller mounted adjacent the second inlet said impeller including blades of the opposite hand to those of the first impeller, a shaft coupling the motor to the impellers, and a heating unit disposed intermediate the impellers and including a frame assembly incorporating a disc having a diameter equal to that of the interior of the casing, and heater elements mounted on the frame assembly.

The invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which:

FIG. 1 is an exploded perspective view of one embodiment of a hair dryer in accordance with the invention; and

FIG. 2 is a perspective view of a modified form of heating unit for the hair dryer of FIG. 1.

Referring now to FIG. 1 the hair dryer comprises a cylindrical hollow casing 10 arranged to be held in the hand and formed from two semi-cylindrical shells 12, 14 which are arranged to mate at longitudinal edges. An electric motor 16, switch 18, and terminal block 20 are mounted in a lower (as shown) portion of the casing 10, a drive shaft 22 of the motor 16 extending upwardly from the motor and lying on the longitudinal axis of the casing. An upper (as shown) end portion of the shaft 22 is journalled in a self-aligning bearing 24 carried by a projection 25 of the casing 10.

The upper end of the casing is open and forms a first air inlet 30. A second, annular, air inlet 32 is formed in the casing immediately above the motor 16. A first, axial flow, fan impeller 34 is mounted on the drive shaft 22 just below the first inlet 30 and above the bearing 24, and a second, axial flow, fan impeller 36 is mounted on the drive shaft 22 just above the second inlet 32. The blades 38, 40 of the impellers 34, 36 are of opposite hand so that rotation of the impellers causes air to be drawn into the casing through the respective adjacent inlets 30, 32.

An air outlet 42 is formed in one semi-cylindrical shell 14 of the casing in the portion thereof lying between the impellers. As shown, the outlet is in the form of two rows of parallel slots 44, the slots extending transversely to the casing axis. Preferably, bristles 46 arranged in semi-annular rows are located between adjacent slots in each row.

A heating unit 50 for heating the air prior to discharge from the outlet 42 is mounted in the casing between the impellers 34, 36 and comprises a frame assembly 52 carrying helical heating elements 54. The heating elements 54 extend longitudinally of the casing and each element 54 is supported at its end portions and its central portion by transverse plate members 56. The plate members forming parts of the frame assembly also serve to direct the air flow within the casing towards the outlet 42. Preferably, the central plate member 56 is in the form of a disc having a diameter equal to the internal diameter of the casing in order substantially to isolate the air flows of the two impellers.

In a modified form of heating unit as shown in FIG. 2, heating elements 60 are helically wound on longitudinal support strips 62 which are carried by a single plate member 64, preferably, this plate member 64 is in the form of a disc which acts substantially to isolate the air flows of the two impellers.

As shown, the motor 16, switch 18, terminal block 20, and the projection carrying the self-aligning bearing 24 are mounted within one semi-cylindrical shell 12 of the casing, and the outlet 42 is formed in the other shell 14.

The operation of the hair dryer is largely self-explanatory, air being drawn in by the opposite-handed impellers 34, 36 through respective inlets 30, 32, heated by the elements 54 or 60 and delivered through the outlet 42.

The features of the hereinbefore described hair dryer ensure a better air flow distribution through the outlet 42 because of the use of two impellers, and the bristles 46, although optional ensure that the hair being dried is constantly re-distributed and is thus all subjected to the action of the hot air. The disposition of a fan impeller 34 and one air inlet 30 adjacent the motor 16 will aid in cooling the motor, and indeed to some degree air passing through impeller 34 will be pre-heated. At the same time the handle (lower) portion of the casing will be cooled and thus more comfortable to hold.

The arrangement of the casing in two semi-cylindrical shells considerably simplifies assembly and the arrangement of all the working parts in one shell aids in the detection of any faults.

Claims

I claim:

1. A hair dryer comprising

an elongate hollow cylindrical casing including

a first substantially semi-cylindrical shell, and

a second substantially semi-cylindrical shell,

said casing defining a first air inlet at one end and a second air inlet intermediate the length of the casing, and an air outlet in the wall of one said shell intermediate the two inlets,

a motor mounted in the other said shell at a location between the second inlet and that end of the casing remote from the first inlet,

a first, axial flow, fan impeller mounted adjacent the first inlet, said impeller including

blades of one hand,

a second, axial flow, fan impeller mounted adjacent the second inlet said impeller including

blades of the opposite hand to those of the first impeller,

a shaft coupling the motor to the impellers, and

a heating unit disposed intermediate the impellers and including

a frame assembly incorporating

a disc having a diameter equal to that of the interior of the casing, and

heater elements mounted on the frame assembly.

2. In a blower device,

an elongate hollow casing comprising

a first substantially semi-cylindrical shell, and,

a second substantially semi-cylindrical shell,

said shells mating at their longitudinal edges,

a first fan impeller located adjacent one end of the casing and carried by said first shell independently of said second shell,

a second fan impeller spaced axially of the casing from the first fan impeller and carried by said one shell independently of said second shell,

the first and second fan impellers being arranged to produce opposed air flows within the casing,

said casing defining a first air inlet at one end, and

a second air inlet intermediate the length of the casing,

driving means for the impellers carried by said one shell independently of said second shell, and

said casing having an outlet for air flows produced by said fan impellers between the inlets.