GB2038623A

GB2038623A - Improvements in or relating to portable hair care apparatuses

Info

Publication number: GB2038623A
Application number: GB7942476A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-12-08
Filing date: 1979-12-10
Publication date: 1980-07-30
Also published as: IT7909618A0; AU5345279A; FR2443224A1; FR2443224B1; DD147617A1; AR217216A1; NL7908855A; IT1166035B

Abstract

A portable hair care apparatus for providing directional radiation and forced convection comprises a casing 1 having air inlet openings 5 and slots 7 and an annular concave reflector 18 spaced from the inner wall of the casing, an annular electrically heated infra-red radiator 20 being arranged adjacent the reflector and constituting the sole heat source. An air-guiding and protective grid 8 is disposed in front of a forward opening of the reflector 18 and provides the casing outlet openings. An electric motor 13 in the casing 1 is received by a holder 12, which extends within the reflector 18, and drives an axial fan 11 which is rotatable at least partially within the reflector 18. In a modification the reflector is partly cooled by air drawn through the front peripheral openings of the casing. <IMAGE>

Description

SPECIFICATION Improvements in or relating to portable hair care apparatuses The invention relates to a portable hair care apparatus for providing directional radiation and forced convection ofthetype having an infra-red radiator as the sole heat source and a fan driven by an electric motor in a casing which is provided with inlet openings and blow outlet openings for air.

It is known that light in the infra-red region of the spectrum possesses a great penetration depth as heat radiation.

For the care of human hair, hot air apparatuses are in use which are equipped nearly exclusively with a heating arrangement and a fan. Such apparatus generally serve for drying wet hair but, in conjunction with attachable devices, such as brushes and combs, they may also be used for dressing hair. In order to shorten the treatment periods, the heat output, and therefore necessarily also the blower output (m3/min), have been steadily increased. The very hot air stream can be tolerated by the hair only as long as it is still wet, but the user cannot assess exactly the instant of drying. The high flow speed disarrays the hair and is unsuitable for loose hairdoes.

The problem in the use of an infra-red radiator as the sole heat source resides in the control of the temperatures occurring in its immediate vicinity.

There thus arises the problem of finding ways and means for developing a hair care apparatus of the kind referred to above, to form a compact conveniently manipulated apparatus which is not only portable, but may also be handled in a convenient manner. A condition forthis is that in spite of the radiation loading by the inner heat source the temperature of the casing and the flow speed of the air remain low. Apparently these two conditions contradict each other, because the air conveyed by the fan serves at the same time for internal cooling of the apparatus.

According to the invention, there is provided a portable hair care apparatus for providing directional radiation and forced convection comprising a casing provided with an inlet and blow outlet opening for air, an annular concave reflector which has a forwardly drawn side wall and which is retained at a spacing from the inner wall of the casing, an annular electrically heated infra-red radiator as the sole heat source arranged in the focal line of the reflector, an air-guiding and protective grid which is arranged in front of a forward opening of the reflector and provides the air flow outlet openings of the casing and an electric motor in the casing received by a holder which extends within the reflector, the motor being arranged to drive an axial fan wheel which is rotatable within the reflector.

The reflector can surround the infra-red radiator as far as possible and reflects forwardly and outwardly and rearwardly directed radiation thereof.

The reflector is retained at a spacing from the inner wall of the casing in order to avoid direct heat transfer by body conduction and in order to maintain a low casing temperature. All component parts located within the radiation region of the infra-red radiator, with the exception of the axial fan wheel, may have radiation reflecting surfaces.

For the purpose of cooling the casing, the arrangement may be made so that either the reflector is cooled on both sides by external air which is sucked in through peripheral openings of the protective grid atthefrontofthe casing, orthatthe suction inlet openings at the back of the casing extend over the entire region of the reflector, that is to say not only over its rearward (small) opening through which the air which is sucked in by the axial fan wheel flows into the interior of the reflector, but also over the reflector ring itself. It is attained thereby that cool external air is sucked into the rear opening also out of the gap between the reflector and the casing and cools the reflector ring also on its outer surface which radiates towards the inner wall of the casing, i.e. lowers its temperature.The ratio of the air quantities sucked in directly and indirectly may be determined by the configuration of the suction inlet openings in the surface parts of the rear wall of the casing which are associated with the rear reflector opening on the one hand and the reflector ring on the other hand, and by the position of the fan wheel, a ring of scoops of which has a certain axial extent, in or in front of the reflector opening.

In a preferred embodiment of the invention, the fan wheel has a surface which does not reflect radiation, that is to say it has approximately the properties of a black body. Preferably its ring of scoops has a dull black surface. Thereby return reflection of the portion of the heat radiation which falls on to the fan wheel upon the holderforthe motor which extends within the reflector, and prohibitive heating of holder and motor are prevented. The same effect could be obtained by cooling by means of the blower air flow ing over the holder, but only with a considerably and undesirably higher air output of the blower. Thus this blackening of the fan wheel is a considerable contribution to the desired compactness of the apparatus.The heat absorbed by the fan wheel is delivered directly to the air flowing through its ring of scoops, before this air enters into the reflector interior with its infra-red radiator, i.e. the hot zone.

After further heating, the air discharges mildwarm drying air at the front end of the apparatus.

In a preferred embodiment of the front end of the apparatus, the protective grid comprises a number of concentric rings which are supported by a number of radial ledges and which are arranged inside and outside the diameter region of the infra-red radiator and are connected to each other and to the motor holder by the radial ledges. Therefore the radiation of the infra-red radiator travels through the protective grid in a largely unimpeded manner (except for the few narrow radial ledges).

The protective grid, the ledges and the holder of the motor are preferably constructed as a unitary metallised moulded member of synthetic resin material. The mirror surface reflects the proportion of the infra-red radiation impinging upon it outwards through the protective grid in the front end of the apparatus.

The motor, advantageously a low voltage direct current motor, can be largely screened against the heat radiation by means of the holder surrounding it, but is heated by its own loss heat. Therefore, the motor may be located in a box which is secured in the motor holder with the formation of an annular air gaps and provided with a plurality of longitudinal slots which are uniformly distributed over its periphery for the passage therethrough of the cooling air. Thereby the attachment of the motor in the casing may be effected independently of the motor type; a simple press fit between a few ledges extending on the inner wall of the holder in the longitudinal direction thereof would be insufficient at the considerable temperature differences which occur between use and non-use and the heat expansions caused thereby of the synthetic resin components.On the other hand the annular gap formed between the box and the holder may be arranged optimally in relation to the ring of scoops of the axial fan wheel likewise in a manner independent of the motortype.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which: Figure lisa longitudinal section through an apparatus on the axis of its handgrip; Figure 2 is a rear view of its casing; Figure 3 is a view of the front of the casing with the protective grid partly cut open; Figure 4 is a cross-section on the line IV-IV of Figure 1 through the motor holder; Figure 5 is a longitudinal section corresponding to Figure 1 through a second constructional form of the apparatus; and Figure 6 is a rear view, corresponding to Figure 2, of the apparatus of Figure 5.

A flat casing 1 is of part-spherical shape at the front and at the back is provided with a handgrip 2 which is located at a manually convenient angle to the casing. The casing and the handgrip are formed by two half-shells 3,4 of synthetic resin material (Figure 1). The rear half-shell 3 comprises a centre field provided with openings 5 and a ring field which is concentric therewith and is provided with slots 7, the ring field having approximately the diameter of a reflector 18 (Figure 3).

A protective grid 8 produced from metallized synthetic resin material is inserted in the forward half-shell 4 and consists of a plurality of concentric rings 10 which are held by three radial ledges 9 (Figure 3). Because of their axial length, the rings 10 operate as air guides for the air stream produced by an axial fan wheel 11 and partially as a radiation protection for a central holder 12 for a motor 13 which drives the fan wheel (Figure 1).

A ring of scoops 14 of the fan wheel 11 has a dull black surface and consists preferably of black anodised aluminium. It is secured on the shaft of the motor 13 by means of a hub 15 of synthetic resin material.

The motor 13 is located in a box 6 of synthetic resin material which is pushed into the holder 12 and retained therein by means of a detent connection in a manner not illustrated in detail. The outer diameter of the box 6 is smaller than the clear measure of the holder 12; so that an annular air gap 16 is formed between the two which is open at the front end of the protective grid 8. Consequently the fan wheel 11 produces a cooling air stream through this annular gap. The box 6, moreover, is provided with a plurality of longitudinal slots 17 which are uniformly distributed over its periphery (Figure 4) so that the cooling air has direct access to the stator of the motor 13.

Owing to the double enclosure ventilated from behind by means of the annular gap 16 and consisting of the box 6 and the holder 12 the surface of which is additionally mirror-coated, the motor 13 does not become objectionably hot, even during prolonged operation, in spite of the small spacing from the heat source.

The annular, concave mirror-like reflector 18 is inserted by means of the slightly flanged edge of its forward larger opening into the forward half-shell 4 in such a manner that it remains at a distance from the rear half-shell 3 (Figure 1). The external air has access into the annular cavity thus formed through the slots 7 of the ring field. The fan wheel 11 rotates in the rear opening 19 of the reflector 18. Primarily it sucks in air through the openings 5 of the centre field which, as may be seen from Figure 1, has approximately the diameter of the fan wheel, and secondar ilythrough the slots 7 of the ring field; thus also the reflector 18 is ventilated from behind.

A quartz radiator 20 is arranged as an infra-red radiator in the focal line of the reflector 18 (Figure 1).

The quartz radiator is mounted on three supports 21 formed by sheet metal strips angled in Z-shape and engaging the edge of the rear opening 19. The quartz radiator 20 is retained on each of these supports by a clip 22. The three-point mounting is therefore yielding for temperature-based changes of the length and the diameter, respectively, of the quartz radiator.

As shown in Figure 1, the annular quartz radiator 20 is completely screened from the rear half-shell 3, to which it is located nearest because of the compact arrangement, by the annular reflector 18 with its edge drawn up and by the fan wheel 11 which fills the rear opening 19 thereof, whereas in the axial direction of the casing 1, or in the direction of the air stream flowing around the holder 12 of the motor 13 and issuing through the protective grid 8, respectively, it "sees through" between the rings 10 of this grid. The forwardly and inwardly diverging partial radiation of the quartz radiator 20 is projected by mirror action forwardly in the direction of use by means of the metallic shiny surfaces of the holder 12 and the rings 10.

In the constructional example of Figures 5 and 6, the casing 31 is likewise formed by two half-shells 33,34. The rear half-shell 33 (Figure 6) is equipped with slots 35 which extend over an approximately circular area having the diameter of the rear small opening 38a ofthe reflector 38 (Figure 5).

In this embodiment the reflector 38 does not engage closely by its edge the forward half-shell 34, but forms an annular gap 37 together therewith.

The axial fan wheel 41 is arranged in the space between the rear reflector opening 38a and the annular quartz radiator 20. The motor 13 is located in a box 36 which in turn is arranged concentrically in a holder 32. The holder 32 is part of the forward pro tective grid 39, screens by its metallised surface the radiation of the quartz radiator 20 and forms together with the box 36 an annular gap 42.

The electricity supply is effected through the handgrip 2 by means of a cable 43. A slide switch 44 is located in the handgrip, and e.g. two heating stages for the quartz radiator 20 and two or more rotar speeds of the fan wheel 41 may be switched thereby.

In comparison with known hot air care apparatus, the fan wheel 41 rotates at a moderate rotary speed even in the highest stage, and causes little noise. It sucks in cooling air on the one hand at the front through peripheral openings 39a of the protective.

grid 39 and on the other hand at the back though the slots 35 of the rear half-shell 33 (Figure 5). The cooling airsucked in at the front flows partlythrough the annular gap 37 outside around the reflector 38 to the rear opening 38a thereof, partly inside the reflector directly to the fan wheel 41. Thus the reflector 38 is cooled on both sides. A small part of the air conveyed by the fan wheel flows in the casing 31 through the annular gap 42 for cooling the motor 13, a larger part of the air flowing past the quartz radiator 20 and out through the protective grid 39.

The position of the axial fan wheel 11,41 which owing to the compactness of its ring of scoops has a certain axial extent, in the rear opening 19 ofthe reflector 18 (Figure 1), or within the reflector 38 (Fig ure 5), respectively, determines the configuration of the air stream within the reflector in the region of the hot quartz radiator 20 and then in the casing cavity in front of the latter, the number and the axial extent of the rings of the protective grid 8,39 having an influence in the sense of a certain laminar arrangement of the outflow from the grid. All the surfaces exposed to the radiation must be cooled uniformly, the fan wheel 11,41 which absorbs relatively much radiation heat by its black surface cooling so-tospeak by itself.With a given position of the fan wheel, the extent of the ventilation from behind and thus the cooling of the reflector 18,38 is determined by the arrangement and the relative opening ratio of the air inlet openings 5 and 7 in the fields of the rear half-shell 3 of the casing 1 (Figure 2) or 35, respectively, in the rear-half shell 33 and 39a at the front of the casing 31 (Figure 5).

The combined radiation- and ventilation-related measures render possible, in spite of the extremely high temperature lying in the visible red range of the spectrum and above of the quartz radiator, a compact, light hair care apparatus which therefore can be handled without tiring and by means of which the hair can be treated with heat radiation and hot air having a pleasantly low temperature and velocity.

The irradiated hair portions are heated uniformly and simultaneously kept in continuous gentle motion by a mild hot air stream. The apparatus is therefore particularly suitable for air-dried hairdoes.

An embodiment of such apparatus has the following parameters: Casing weight (including handgrip and electrical con structional components) 175 9 diameter 125 mm thickness 60 mm volume (without handgrip) 450 cm3 Infra-red radiator ring diameter 95 mm tube diameter 7 mm output 500 W max.

Axial fan wheel diameter 70 mm airoutputapprox. 141/sex air velocity (at opening width of the protective grid of 105 mm) approx. 2.5 mlsec airtemperature at the protective grid approx. 55"C

Claims

1. A portable hair care apparatus for providing directional radiation and forced convection, comprising a casing provided with inlet and blow outlet openings for air, an annular concave reflectorwhich has a forwardly drawn side wall and which is retained at a spacing from the inner wall of the casing, an annular electrically heated infra-red radiator as the sole heat source arranged in the focal line of the reflector, an air-guiding and protective grid which is arranged in front of a forward opening of the reflector and provides the air blow outlet openings of the casing, and an electric motor in the casing received by a holder which extends within the reflector, the motor being arranged to drive an axial fan wheel which is rotatable within the reflector.

2. A hair care apparatus as claimed in claim 1, in which, with the exception of the axial fan wheel, all component parts located in the radiation region of the infra-red radiator possess radiation reflecting surfaces.

3. A hair care apparatus as claimed in claim 1 or 2, in which the axial fan wheel which has a ring of scoops with a dull black surface.

4. A hair care apparatus as claimed in claim 3, in which the ring of scoops consists of aluminium which is anodised dull black and is secured to a hub of synthetic resin material.

5. A hair care apparatus as claimed in any one of the preceding claims, in which the axial fan wheel is arranged within a rearward opening of the reflector.

6. A hair care apparatus as claimed in any one of the preceding claims, in which the reflector is arranged to be cooled on both sides by external air sucked in through peripheral openings of the grid.

7. A hair care apparatus as claimed in any one of the preceding claims, in which the suction inlet openings at the back of the casing extend overthe entire region of the reflector.

8. A hair care apparatus as claimed in any one of the preceding claims, in which the protective grid comprises a plurality of concentric rings which are supported by a plurality of radial ledges, which are arranged inside and outside the diameter range of the infra-red radiator and which are connected to each other and to the motor holder.

9. A hair care apparatus as claimed in claim 8, in which the protective grid, the ledges and the holder are in the form of a unitary metallised moulded member of synthetic resin material.

10. A hair care apparatus as claimed in any one of the preceding claims, in which the motor is located in a box which is secured in the holder with the formation of an annular air gap and which is provided with a plurality of longitudinal slots uniformly distributed over its periphery.

11. A hair care apparatus as claimed in any one of the preceding claims, in which the infra-red radiator is mounted, by means of clips, in the focal line of the reflector on three sheet metal strips bent to form supports which are formed on the edge of the rear opening of the reflector and are uniformly distributed over the periphery.

12. A hair care apparatus as claimed in any one of the preceding claims, in which the infra-red radiator is an annular quartz radiator or ceramic radiator.

13. A portable hair care apparatus substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 4 or Figures 5 and 6 ofthe accompanying drawings.