This invention relates to climate chambers and more particularly to steam rooms, sauna rooms and steam cubicles.
Climate chambers are well known and provide an enclosed space which may be filled with steam so as to produce a typical working environment of around 100% Relative Humidity at temperatures of about 40-42°C, although up to 50°C can sometimes be tolerated. Such chambers provide an environment which is considered to be advantageous to the user, although the temperature range specified can vary according to choice and may indeed be much lower than those just mentioned or may have an upper limit of 125°C with a Relative Humidity of only 1 or 2%.
It is known to use an external boiler to provide the steam for climate rooms via suitable pipework. In alternative arrangements a vessel containing water is provided low down in the climate room and a heating element similar to those used in electric kettles is employed to boil the mass of water in the vessel. In both of these systems a mass of water has to be heated before producing any steam and there is, therefore, a considerable delay in achieving suitable conditions within the room.
In CH-A-0503959 there is provided a climate chamber comprising substantially impervious walls and incorporating one or more steam producing devices, the or each steam producing device comprising a member adapted to be heated and a water flow device whereby a controlled flow of water from the flow device is caused to contact the member thereby to produce steam substantially immediately upon contact with the member, the heat produced by the member and the water flow rate being set or controlled relative to each other.
The present invention is characterised in that control means are provided for selectively varying the flow of water from said water flow device and the heat produced by the heated member wherein the heat produced by the member is always just sufficient to ensure that the rate of production of steam is substantially equal to the rate of flow of water.
The term climate chamber, as used herein, means any chamber within which the humidity may be varied from 0 to 100%. Relative Humidity and the temperature varied from ambient to 125°C. Examples of such climate chambers include steam rooms (e.g. saunas) and steam cubicles.
The heat produced by the member and the flow of water may be independently variable so as to provide any combination of Relative Humidity and temperature within the chamber. The member may heat the space within the chamber directly and/or through the production of the steam which is released into the chamber. The chamber may include one or more further heaters so as to provide another way of increasing the heat of the chamber independently of the amount of steam required.
Preferably the water flow device is positioned above the member so that water falls under gravity on to the member. In an alternative embodiment of the invention, the water flow is delivered by a controlled pump or mains water pressure with, optionally, a flow control valve and the water flow device may provide a spray of water droplets (e.g. by passing the water flow through a nozzle) which may be directed at the member at any angle and from any direction. Conveniently the or each steam producing device is located within the chamber and near the floor of the chamber. Ideally, an inner casing extends over the top and sides of the device and an outer casing extends over the top and the sides of the inner casing.
In other arrangements an inner casing surrounds the top, base and sides of the or each steam producing device and is provided with one or more steam outlet holes and an outer casing extends over the top and sides of the inner casing and is also provided with one or more steam outlet apertures. In a preferred case the inner casing is provided with an indentation below one of said apertures for receiving a fragrance release material.
In another embodiment of the invention, the outer casing extends over the top and sides of the steam producing device and comprises one or more steam outlet apertures which include at least one substantially vertically extended portion. Preferably the extended portion reduces the temperature of the steam and air mixture passing therethrough to, for example, below 75°C, preferably below 70°C (e.g., between the temperature of the chamber and 60°C).
In preferred arrangements the inner casing is made from metal and the outer casing is made from plastic.
In some embodiments the or each steam producing device is located externally of but adjacent the chamber. In one, the or each steam producing device is located below the floor of the chamber and the floor has a waste outlet through which the steam enters the chamber. With another, the or each steam producing device is located above the ceiling of the chamber and circulation means is provided to circulate the steam within the chamber.
In preferred arrangements the member comprises a metal block incorporating a heating element. Conveniently the block is made of aluminium, and the heating element is mineral insulated and is cast on to the block, said element being heated electrically. Control means is preferably provided for the member and this control means may incorporate an overtemperature switch.
Ideally, a control system is provided in the chamber and incorporates preferably a manual control for the desired chamber temperature and humidity and a manual control for the desired length of time in the chamber. Controls may also allow for programmed operation at different operating conditions for chosen periods of time.
It is a preferred feature that regulation means is provided to regulate the flow of water. The flow will depend largely on the temperature of the member and the dispersion of the water over the heated member. In some arrangements the regulation means incorporates a solenoid valve and a constant head device or a constant displacement pump or mains water pressure with flow control.
A detailed embodiment of the invention will now be described in more detail. The description makes reference to the accompanying diagrammatic drawings in which:
Figure 1A shows a corner 10 of a steam room having a base 11 and a side wall 12. The remainder of the steam room is not shown, but the room is constructed principally from impervious materials such as stone, tile, plastic, etc. so that the steam is not absorbed by the walls. However, if a sauna room with higher temperatures and lower humidity is required, the walls can be constructed from other materials such as timber. There is also shown a steam generating device 13. The device is located a short distance from the base 11 and is attached to the side wall 12 of the room.
The device 13 incorporates an aluminium block 14 which is bolted at 15 to the side wall 12. In plan view the block 14 is generally rectangular and has an electric heating element (not shown) cast on to it or fixed to it. In this example the heating element is mineral insulated and has an electrical connection 16 which projects through an opening 17 in the side wall 12. There is also an overtemperature switch 18 for protecting the heating element.
The device 13 also incorporates a water supply via a pipe 19. The flow of water is controlled by using a solenoid valve 20 and exits via a water flow control device 21. The upper part of this device 21 is cylindrical and a constant head of water is maintained in this part. A steady flow of water exits from the lower part of the device 21 and any excess goes to waste via an overflow pipe 36.
An inner casing 22 is made from stainless steel and extends over the top of the block 14 and around the exposed sides. An outer casing 23 is made from plastic and extends around and spaced from the top and sides of the inner casing 22.
In use the block 14 is heated very quickly by the heating element and the carefully controlled flow of water falls under gravity on to the block. On contact with the block the water immediately becomes steam which is forced by virtue of the inner casing 22 downwards and out into the room. This continues until the desired temperature and humidity in the climate room is reached.
The flow of water and the temperature of the block 14 are carefully monitored and controlled for comfort and safety. A control panel would be provided in the room so that the user can decide upon the temperature and humidity he wants the room to be at and also the length of time he wishes to be in the room. The user enters the room, sets the controls and the flow of water and the block temperature will be controlled so that when the desired humidity and the desired temperature are reached, the steam generation and/or heat output may be modified so as to maintain the desired climate. The flow of water and the temperature of the block may be controlled so as to maximise efficiency, the block being heated just enough to ensure immediate evaporation of all the water supplied with little or no wastage. Ideally the user enters the room at the beginning of steam and/or heat production so as to rise in temperature with the room. This avoids the shock of entering the hot room and also avoids losing climate when a door is opened.
The control panel could also be adapted to give a programmatic cycle of temperatures and humidity if desired and could be located inside or outside the room.
Figure 1B illustrates an alternative embodiment of the invention in which the outer casing 23 comprises a vertically extended portion 68. The vertically extended portion 68 provides a passage 80 through device 13. In use, air is drawn up through the lower end of passage 80 by convection, meets steam passing into the passage 80 through aperture 83 in inner casing 22 and exits into the steam chamber through the top end of passage 80. This arrangement allows the temperature of the steam/air mixture to be reduced before it enters the chamber. The portion 68 may be positioned at any point along the top of the outer casing 23.
Figure 2 shows that an example of the present arrangement reached an acceptable "steam bathing" temperature in 7 minutes, normal body temperature being reached in 5 - 6 minutes and a comfortable temperature of 25°C being reached in less than 3 minutes. Similar temperatures took much longer to achieve in a comparable 'kettle' type steam generator. On the graph X represents the normal steam bathing temperature range.
The climate room may also incorporate a conventional shower head and may be in the form of a combined shower/steam cubicle. It is also envisaged that the idea could also be applied to steam or sauna chambers which do not entirely enclose the body, for example cabinets where the head of the user remains outside.
In one working example of the above steam/heat generating device 13, the outer casing 23 projects through the side wall 12 and extends generally along an adjacent sidewall. The outer casing of this example is only about 40 mm wide and is some 350 mm long and 100 mm high. This example is by no means limiting but illustrates the possible compactness of a suitable efficient arrangement.
Figure 3 shows an arrangement which is similar in many respects to that shown in figure 1 and so like parts have been given like reference numerals. In this arrangement the stainless steel inner casing 22 has two steam outlet holes 30 and the outer plastic cover 23 has a steam outlet hole 31. Directly below the hole 31 is an indentation 32 in the casing 22 for receiving a fragrance release material if desired, the heat from the block 14 vaporising the material.
The steam/heat generating device 13 shows an electric heating element 33 encased in the aluminium block 14 which is formed with a shallow recess 34 in its top surface and a slope 35. The flow control device 21 is of a constant head variety and any overflow goes to waste via overflow tube 36. The outlet 37 of device 21 is disposed above the top of the slope 35 so the water flows down the slope thereby maximising the potential of the heated block 14.
It will of course be appreciated that the location of the heated block within the chamber itself means that no energy is wasted.
In figure 4 the steam/heat generator 13 is mounted just on the outside of the wall 12 but the steam/heat outlet 38 leads directly to the inside of the chamber. This arrangements results in no loss of space in the chamber.
In figure 5 the steam/heat generator 13 is located directly below the floor 11 in say a shower cubicle. In this example the steam outlet 38 opens to the shower waste hole 39 in the floor 11, as does the overflow tube 36. This arrangement is advantageous in that there is no loss of space in the chamber and steam/heat is introduced at the lowest possible level.
Figure 6 shows a roof mounted generator 13 which lends itself to being an add-on feature for an existing shower cubicle for example. This generator 13 requires a circulation mechanism and the figure shows an example in the form of a centrifugal fan 40. This system tends to ensure a good temperature gradient throughout the chamber. Recirculation of air within the chamber is provided by aperture 96.
In figure 7 the steam/heat generator 13 is located outside the steam chamber, a discharge duct 50 directing the steam/heat into the chamber at floor level in this example. A centrifugal fan 51 forces the steam/heat produced by the generator 13 into the chamber. The duct 50 also carries any waste water from the flow control device 21 and any condensed water vapour into the chamber where it can flow into the water outlet of the chamber. The arrangement is contained in an insulated casing 52 so that the mixture loses as little heat as possible.
Also shown is an optional suction duct 53 having a variable port. The centrifugal fan 51 pulls air from the chamber and effectively reheats it by virtue of it passing by the generator.
To the skilled person, it will be apparent that many other arrangements are possible.
The steam/heat generating devices of the present invention do not have a free volume of boiling water within the chamber. With known 'kettle' generators there may be up to 4 litres of boiling water in a plastic container and should the user fall the consequences could be particularly dangerous. The only contact with the present generator is contact with the plastic outer casing 23. This casing operates at a temperature a little over the enclosure temperature and the only free water is cold water during normal running. There may, however, be some free water that is heated during starting up.
The present arrangement is also quiet in operation because the steam escapes from a large area at the base of the generator or elsewhere. With 'kettle' type generators the bubbling of the boiling water is quite loud in comparison as is the noise from the nozzle of an external boiler.
In addition the steam generating device is easy to maintain and replace. In particular it is easy to clean the element in hard water areas and to replace the block 14/element in the event of failure.
It will be appreciated that the heating element/block can be of any suitable size or shape depending on the desired effect. Also the materials of manufacture of the various components could be altered where necessary. Also more than one device 13 could be used in a single chamber.
Also the block could be heated by means other than electricity. For example, it could be heated by means of a butane gas cylinder or other suitable gas means. The device 13 could also be used with a water container providing water to the water flow control device 21. A suitable combination of these with a suitable cubicle could result in a portable climate room.