EP0524168B1

EP0524168B1 - Electric fan for heating and humidifying

Info

Publication number: EP0524168B1
Application number: EP90907378A
Authority: EP
Inventors: Gianfranco Giudici
Original assignee: ERMETE GIUDICI Srl
Current assignee: ERMETE GIUDICI Srl
Priority date: 1990-04-13
Filing date: 1990-05-18
Publication date: 1994-01-19
Anticipated expiration: 2010-05-18
Also published as: DE69006222D1; IT9020041A0; EP0524168A1; WO1991016579A1; IT9020041A1; DE69006222T2; IT1240430B

Abstract

Electric fan (10) that comprises a fan (19), electric elements (22) for heating the air (63) and a vaporizer with boiler (42) and electric element (52), the steam (64) emerging through small holes (28) made immediately below a grid (14) through which a draught of air (63) comes out horizontally so as to obtain humidified air (65) by spontaneous mixture of the air (63) and the steam (64) directly outside the apparatus (10) due to the fact that the steam (64) rises.

Description

The invention concerns an apparatus for heating and humidifying air in an internal environment.
Objects in everyday use are electric heater fans, namely electric stoves with forced convection that, by means of an electrically operated fan, set up a stream of air around incandescent electric heating elements.
The air enters cold and comes out warm.
Also in everyday use are humidifiers, namely apparatuses for moisturizing the air that is too dry in homes or places of work, such as for example those with a "wetted surface" wherein a surface wetted by the liquid receives a flow of air with consequent production of steam.
When a room is being warmed, especially with an electric heater fan, it becomes necessary or at least advisable to recover humidity by operating a humidifier.
This means practically doubling costs on account of having to purchase two apparatuses, as well as operational complications in regulating both in their interconnecting effects so as to obtain good air conditioning.
The patent US-A-2 021 521 discloses an air conditioner in which the flow of air generated by a fan, driven by an electric motor, passes over electric heating elements and becomes mixed with steam produced by heating water contained in a boiler.
The steam leaves the boiler at a level higher than that of the electric elements and is conveyed downwards through a curved pipe.
Mixture of the fan-generated hot air with the steam from the boiler takes place inside the apparatus within a chamber created in the body of the boiler situated inside the casing which contains the fan.
Air humidification, as described above, is imperfect bearing in mind the conflict that exists between thrust from the fan and the tendency, as previously stated, of the steam to rise upwards.
Consequently it is also difficult to adjust the degree of humidification or to turn it off.
The patent US-A-4 003 967 discloses a humidifier comprising a chamber inside which there is a fan associated to electric heating elements.
At a level higher than that of said electric elements a small tank of water is placed and heated to produce steam.
The fan draws in air through a grid in the front wall of the apparatus; said air is obliged to flow upwards until it reaches the top of the tank where it mixes with the steam and flows out through apertures made for the purpose in the same wall as that through which cold air enters.
With this apparatus too, air-steam mixing takes place in side the apparatus. The path followed by the air during the heating process and then on up to reach the top of the tank from where it flows out, is so circuitous that efficiency is low and it is also difficult to adjust the apparatus to get the best result from it.
The drawbacks occasioned by the tortuous nature of the path followed by the air are still present even if humifidication is turned off and the apparatus is then used for obtaining hot air only.
The above invention eliminates or greatly reduces these drawbacks as well as providing considerable advantages as will be explained below.
Subject of the invention is an electric fan device according to claim 1, in which the draught of air,generated by a fan worked by an electric motor, enters the apparatus through a rear grid, flows over electric heating elements, comes out through a front grid and is mixed with steam produced by heating water in a boiler by means of electric elements.
The steam emerges through small holes made immediately below the front grid from which the draught of air flows out horizontally.
Air and steam are therefore mixed immediately outside the apparatus since the mass of steam rises spontaneously.
A lateral cavity surrounds the sides of the boiler which lies practically central in a watertight tank of water.
At the base of the cavity and of the boiler there are apertures to allow passage of the water.
The purpose of this is to concentrate the heat, from the electric heating element. inside the boiler, in the water contained in the boiler which water, on becoming steam, is replaced by water from the tank.
Steam generated by the boiler is distributed through the upper hole in a valve formed of a chamber placed on the top of said boiler.
Said valve comprises a heavy ball of a diameter greater than that of said hole and slightly smaller than the width of said chamber.
Therefore, if the apparatus is accidently knocked over, gravity will cause the ball to close the hole preventing water in the boiler, and consequently water in the tank, from draining out and spreading inside the whole apparatus.
The electric heating elements for heating the air are placed in two parallel dials coaxial with the axis of the fan, upstream of said fan, between the rear grid and the fan.
It is an advantage if the electric heater fan comprises a box-shaped body to house the fan and electric elements for heating the air, and if it also comprises a box-shaped base,placed below the box-shaped body, for housing the boiler.
Said body is associated to said base by hooks that can be hooked and unhooked from the outside so that they can be easily taken apart for filling up the tank with water.
The electric controls enable the elements for heating air to be worked separately from the fan and from the heating element inside the boiler for heating the water, so that moisturized air can be obtained either cold or heated as preferred.
The described invention offers considerable advantages.
Air can be heated and humidified at the same time by a single apparatus.
Hot air and steam are produced independently in two separate chambers and, in the same way, leave the apparatus through separate apertures and by means of separate devices.
It is thus possible to adjust humidification as preferred by adequately exploiting the characteristics of the flow of hot air,leaving through the grid in a practically horizontal direction, and the steam which emerges in a practically vertically direction,through holes made for the purpose, and then rises upwards.
The advantages of these maximum adjustment possibilities also apply to the flow of air,continually heated by the fan,due to the presence of virtually parallel and aligned grids at the front and back.
For the user purchases and running costs are lower while in addition environmental air reaches, within a short time, the right temperature and degree of humidity, thus providing an optimum type of air conditioning.
Characteristics and purposes of the invention will be made still clearer by the following example of its execution illustrated by diagrammatic figures.

Fig. 1:: External front perspective of the electric fan device.
Fig. 2:: Section on a vertical longitudinal plane of the electric fan, front view.
Fig. 3:: Section on a horizontal plane of the electric fan, plan view.
Fig. 4:: Section on a vertical transversal plane of the electric fan, side view.

The electric fan device 10 comprises a box-shaped body 11 associated to a box-shaped base 12 the front of which 13 is inclined.
The box-shaped body 11 comprises a front grid 14 with horizontal apertures, a back grid 15 parallel to the first, with vertical apertures, the base 16, the conveyor 23.
The electric motor 17 mounted on supports 18, is fixed co-axially inside the back wall, on said motor's shaft the fan 19 is mounted and, on the supports 21, the crown 20 carrying the pair of electric heating elements 22 arranged on parallel dials coaxial to the axis of the fan 19.
The box-shaped base 12 forms the tank 40 for water 41, said tank being watertight.
Practically in the centre of said tank there is a boiler 42 surrounded by a lateral cavity 44.
The water 41 in the tank 40 can pass inside from said cavity through the lower holes 45, and from there to the boiler 42 through the lower holes 46.
The boiler 42, at the same level as the top of the wall 47, comprises the valve 48 with heavy ball 51, comunicating by the opening 49 with the boiler 42 and by the opening 50 with the cavity 44.
Inside said boiler 42 there is an armoured electric heating element 52.
Between the bottom 16 of the box-shaped body and the top 25 of the base 12 and the top 26 of the boiler 42, is the body 55 comprising the chamber 56 next to the valve 48, communicating with the duct 57 for passage of steam to the small holes 28 made on the front 27 of the box-shaped body 11.
The interposed packing 60 makes a seal between the bottom 16 of the box-shaped body 11, the body 55, the top 25 of the base 12, the top 26 of the boiler 42, the electric heating element 52 and the front 27 of the box-shaped body 11.
There is a hole 61 in said packing where it meets the valve 48.
The box-shaped body 11 is connected to the base 12 by means of the rotatable levers 30 turning on the pins 32 fixed to the sides of said body 11 and comprising the hooks 31 that hook onto the opposite hooks 34 fixed to the supports 35 mounted on the sides of the base 12.
The hooks 31 are pressed against the hooks 34 by the springs 33 acting on the levers 30.
These latter can be worked from outside the box-shaped body 11 through the windows 36.
A transparent window 37 is inserted in the inclined front 13 of the base 12, to show the level of water 41 in the tank 40.
The water in the boiler 42 when heated by the electric element 52 turns into steam which after passing through the opening 49 in the valve 48 and through the hole 61 in the packing 60, enters the duct 57, then passes through the small holes 28 emerging from the front of the box-shaped body 11 immediately below the grid 14 from which emerges the draught of air produced by the fan 19.
Said draught of air is supplied through the rear grid 15 and through the electric heating elements 22.
Therefore, by turning on said elements hot air comes out from the grid 14.
As seen in the figures, the wavelets 63 of air coming from the grid 14 mix with those 64 of steam emerging from the holes 28 and form wavelets 65 of humid air.
If the electric heating elements 22 are switched on, warm moist air will be produced for the internal environment, while if said elements are not switched on, the apparatus will produce cold moist air.
If the apparatus should be accidently overturned, the ball 51 in the valve 48 will alter its position as shown in Fig.4 and will fall by gravity into the position 51' (shown by a dotted line) and in that position it closes the hole 61 in the packing 60 preventing water contained in the boiler 42 and in the tank 40 from spilling out and therefore from spreading throughout the inside of the box-shaped body.

Claims

Electric fan device comprising a grid (6, 7) in the rear wall, a vertical grid (23) in the front wall, a boiler (16) containing water heated by means of electric heating elements (19), a fan (11) situated between the two grids and driven by an electric motor (10) and electric heating elements (12) placed between said fan and said rear grid (6, 7)
characterized in that the boiler (42) communicates at its summit with holes (28) made in the front wall of the apparatus (10) immediately below the front grid (14) so that the draught of air (63) generated by the fan (19) penetrates inside the apparatus through the rear grid (15) and flows out through the front grid (14), mixes with the steam (64) generated by the boiler and comes out through the holes (28) made below the front grid (14) so that humidified air (65) is made available immediately outside the apparatus (10) due to the mass of steam (64) that rises upwards spontaneously.
Electric fan device as in claim 1,
characterized in that the boiler (42) is surrounded on its sides by a cavity (44) and is placed centrally in a tank (40) of water (41), the tank being watertight, there being at the base of the cavity (44) and of the boiler (42) holes (45,46) to allow the water (41) to pass, the purpose of this being to allow the heat from the electric elements (52) inside the boiler (42) to be concentrated in the water inside said boiler, which water is spontaneously replaced, when reduced by its transformation into steam, by the water inside the cavity (44), in turn replaced by water (41) from the tank (40).
Electric fan device as in claim 1,
characterized in that the steam (64) generated by the boiler (42) is distributed through the upper hole (61) of a valve created by a chamber (49) placed at the top of said boiler (42) and comprising a heavy ball (51) of a diameter greater than that of said hole (61) and slightly smaller than the width of said chamber (49) so that, if the apparatus (10) is accidentally overturned, falling by gravity said ball (51) spontaneously closes the hole (61) thus preventing the water inside the boiler (42) and therefore that in the tank (41) from spilling out and flowing round inside the apparatus (10).
Electric fan device as in claim 1,
characterized in that the electric heating elements (22) for heating the air are arranged on a crown (20) in two parallel dials coaxial to the axis of the fan (19) and upstream of said fan, between the rear grid (15) and the fan (19).
Electric fan device as in claim 1,
characterized in that it comprises a box-shaped body 11 for housing the fan (19) and electric elements (22) for heating the air, and comprises a box-shaped base (12) for housing the boiler (42) placed below the above box-shaped body (11), said body (11) being held to said base (12) by hooks (31) that can be worked from outside for temporary separation of the body from the base in order to fill the tank (40) with water.
Electric fan device as in claim 1,
electric elements (22) for heating the air (63) can be turned on separately from the fan (19) and the electric element (52) in the boiler (42) for heating the water (41), and this in order to provide humidified air (65) either hot or cold as preferred.