STEAM GENERATING ASSEMBLY FOR CONTROLLING THE MOISTURE CONTENT OF AIR

Abstract: A steam generating assembly adapted to control the humidity in air in a room (4) to a desired level, and comprising a steam coil sling or two or more parallel steam coil slings (2) which are arranged to be mounted in direct or indirect contact with a heat generating means or close to same, and which coils can, in any desired number, be supplied with water (1) which becomes evaporized in said steam coils (2) actuated by the heat from the heating generating means and which, after having been evaporized to form steam which is issued to the room (4) through a distribution chamber (3) and a steam tube (5), and which distribution chamber (3) is connected to a return channel (6) in which drops of water and condensed water is returned to the water distribution chamber (3), whereupon the steam (5) is directly issued to the air of the room (4) intended to get an increased humidity.

Description: STEAM GENERATING ASSEMBLY FOR CONTROLLING THE MOISTURE CONTENT OF AIR The present invention relates to a steam generating assembly arranged to control the moisture content of air in closed rooms to a desired level. The invention has been especially developed as the solution of maintaining the moisture content (humidity) in domestic rooms and/or in a sauna at a desired high level, but it is obvious that the invention is as well suitable for increasing and controlling the moisture content in all kinds of other places like in housings, storerooms and other places where the humidity has a tendency of getting an unsuitably low level. In the following the invention will mainly be described with reference to an assembly which is operated by electric radiation heating like electrical heater elements or electrical sauna heater units, but it is obvious that the heater unit may as well be operated by other types of heating means which provide such high temperatures that water can be vaporized, for instance in wood burning sauna units, in oil or wood burning central heaters, in hot air heater units etc. In particular in winters the air humidity tends to be very low, and said humidity tends to decrease to as low level as 5-10%, and such low air humnidity is obviously dangerous to health. For normal housing conditions a moisture content of 40-60% is most favourable. In other cases the air moisture content (humidity) may decrease strongly when the locality is heated. This is true for instance in a sauna, in which the air moisture content in many cases may be amount to 40%, or lower, before the heating of the sauna is started. Following the rise of temperature in the sauna the humidity decreases, as illustrated with the lowermost curve line 21 in figure 6, so that the humidity, at full heat of the sauna, which may be about 70-80°C, can be as low as 10%. In many cases attempts have been made to increase the air humidity by splashing water onto the stones which are generally present in the sauna heater unit, but this only has a marginal effect, and it is not possible to increase the air humidity to the desired level in this way. A too low humidity leads to a drying out of the skin and this can be directly harmful. Another existing problem is that it takes a long time to raise the air humidity in a domestic house room and in the sauna. Attempts have been made to provide an increase of the air humidity in a sauna and to keep said humidity at a high level. Thus, US-A-6,771 ,603 discloses an apparatus having a cylindric receptacle containing water, and the top of which is formed as a carrier for sauna stones which are moistened by means of steam coming from the cylindric receptacle. Said apparatus has a very restricted humidity increasing effect and it is not useful for available sauna heater units or other heater units. DE-A-34 04 892 shows a sauna heater unit having electric heating means, which heater unit, at the bottom thereof, is formed with a water heater unit from which steam is issued in the direction upwards, past electric heating coils, and up through an upper carrier containing sauna stones. Said apparatus is complicated and also can not be used as a supplement for available sauna heater units or other heater units. Also DE-A-31 41 820 discloses a sauna heater unit comprising a water container having electric heater elements which provide a vaporization of the water and conveys steam up through a container carrying sauna stones arranged at the top of the sauna heater unit. Said apparatus is disadvantageous in the same respects as the latest above discussed apparatus. The object of the invention therefore has been to solve the problem of providing an air moistening unit which can be used in combination with, or as a supplement to, many different types of heater units, like heaters operated by electricity, or by burning of wood, coal or oil, and which quickly and simply can be applied to such an available heater unit, and which is formed so as to quickly increase the air humidity, and which preferably is formed so that it is capable of controlling the air humidity to a desired level. According to the invention the air moistening unit comprises a one or more tube coils, for instance a series of two or more parallel tube coils which are supplied with water, which is vaporized by being heated by the heater unit and in which the steam, after the vaporization is issued directly into the air of the room to be humidified. The apparatus is formed so that the water coil is supplied with water to a predetermined height, or so that a selected number or the vertical series of tube coils are being supplied with water, whereby the issued steam can be increased by making use of an increasing height of supply water of an increasing number of operative steam coils. The tube coil apparatus preferably is formed as a flat pack which can be mounted adjacent or more electric heating coils, or directly in the fire space in a wood burning iron stove or in a sauna unit, or directly in the fire place of an central oil heater unit, etc. The air moistening unit may be connected to an adjustable sensor of the air humidity in the room and to a control valve for adjusting the supply of water to one or more of the steam coils. The apparatus also is formed with a means for collecting condensed water and to divert same back to a water container for avoiding splash of hot water out into the room. Now the invention is to be described more in detail with reference to the accompanying drawings in which figure 1 diagrammatically shows a side view of a simple embodiment of an apparatus according to the invention. Figure 2 is a cross section along line ll-ll of figure 1. Figure 3 shows a cross section view similar to that of figure 2 of a triple type tube coil heater according to the invention. Figure 4 diagrammatically, and partly in a cross section view shows a further embodiment of a steam generating assembly according to the invention. Figure 5 shows a cross section view through a sauna apparatus incorporating a steam generating assembly according to any embodiment of the invention, and seen along line V-V of figure 4. Figure 6 is a diagram showing combined curves illustrating possible examples of the moisture content of a humidified room as a function of time and supplied heat. The steam generating assembly shown in figures 1 and 2 generally comprises a water container 1 , in a simple type of apparatus in the form of a bottle containing water and turned upside down in a water supply carrier, and arranged to supply water to a system of steam coils 2 in which water is vaporized and is issued to a distribution chamber 3 in which existing water drops and condensed water is separated, whereupon steam is issued to the room 4 intended to be humidified through a steam tube 5, whereas water drops and condensed water is drained through the upper part of the water distribution chamber which in this respect acts as a return channel 6 for returning crops of water to the water system. The water container 1 is shown connected to a valve system 7 for controlled supply of water to the water distribution chamber 3 so that the water level in said water chamber 3 is on a suitable height for supply of water to the stem coil, or to one, two or more of the steam coils 2 in the system shown in figure 1. The water container 1 may have a level controlling means which is connected to the control valve 7 and which foresees that the water level of the container 1 is maintained at a suitable height. In the simple embodiment of the invention said water container 1 , which is in the form of a bottle, is mounted so that it can be raised and lowered thereby supplying water to any desired height in the steam coil, or to one or more of the steam tube coils starting with the lowest tube coil 2a and a successive number of coils b-e. The vaporization system can be formed as a single type system having one sling of vaporization coils. The embodiment of figure 2, however, is shown as a twin type system having two parallel sets of steam coils 2 both connected to the water distribution chamber 3. The entering parts 2' of the steam coils are connected adjacent the bottom of the water distribution chamber 3, and the coils extend in a zigzag configuration upwards and are, with the top parts thereof 2" connected adjacent the top part of the water supply chamber 3, more exactly at the return channel part 6 thereof. A heater element 8 is mounted parallelly to the steam coils 2 and is adapted to heat the water flowing in said steam coils 2. A heat distribution plate 9 is mounted between said heater element 8 and each of the steam coils 2. A similar plate 10 is mounted on each exterior side of the heater coils for pressing said stem coils into 2 contact with the heat distribution plate 9. In figure 3 there is shown a sandwich type vaporization apparatus formed as a triple set of steam coils 2 extending parallelly with each other and connected to the water distribution chamber 3 on each side of each heater element 8 there is a heat distribution plate 9. A press plate is mounted on each exterior side of each steam coil 2. The three press plates 10 may be enclosed in a casing for the entire steam coil apparatus. Further there may be an insulating material between said press plates and the casing (not shown in the drawings). Figure 4 shows a slightly modified embodiment of the invention. In this case the water supply chamber is formed with a horizontal upper part 3 and a vertical lower part, acting as a return channel for condensed water drops. In the illustrated case the water level of the water container 1 may be controlled using an adjustable hydrometer 11 which controls the humidity in the room and, by information therefrom, the supply of water over the valve system 7 and a water level control means 12. From the water container 1 water is fed, according to the rule of communicating vessels, through a tube 13 to the bottom 14 of the water distribution chamber 3, from which water is supplied to one or more of the steam coils 2. In the illustrated case the apparatus comprises four steam coils, but it is obvious that there may be a greater or less number of coils depending on what variation of air humidification is desired. At a little need of supply of moisture there is only used the lowermost steam coil a, at increasing need of moisture water is supplied by the steam coils a+b, a+b+c and a+b+c+d, respectively. The water is heated in the steam coils 2 (a-d) by being successively passed upwards through the coils as far as to the upper part of the water distπbution chamber 3 in which water drops and condensed water is separated and is returned to the water system via the return channel 6, whereas steam is issued to the room 4 adapted to be humidified through the steam tube 5. The controlling of the humidification capacity is made by supply of water to a varying water height level in the water container 1 , namely in the lowest level to the height 15, and successively higher water levels 16, 17 and 18 of the water distribution chamber 3. At the lowest level 15 water is supplied only to the lowermost steam coil 2a, at level 16 water is supplied to the two lowermost steam coils 2a and 2b, at the water levels 17 and 18 water is supplied to three and four of the steam coils a-c and a-d, respectively. The level control means shown in figure 4 also acts as a protecting means for overheating in case there is a lack of water in the water supply chamber 3. A corresponding means is provided in the at the bottom of the valve system 7 in the apparatus of figure 1 which means is in the form of floating switch which breaks the current to the heater element or elements if the water level is lower than said switch. In figure 5 is shown one - out of many possible - examples of how the steam generating assembly can be mounted in an available heat generating apparatus, in the illustrated case an available sauna apparatus having two electric heater elements 8a and 8b in a chamber 19, and outside said heater elements compartments with sauna stones 20. The entire steam generating assembly is simply introduced in the sauna apparatus in between the electric heaters 8a and 8b. For distributing the heat, and also for protecting the steam coils against direct contact with the heater coils 8a and 8b the heat distribution plates 9 which are of some well heat conducting material, like copper, are mounted on each side of the steam coils 2, for instance in that said plates are rivet connected on each side of said steam coils 2. As previously mentioned the steam generation assembly may alternatively be used also for other available heating apparatus, like in the stove apparatus or another heat issuing unit or even directly in the fire of a wood burned sauna, an iron stove or in or above/aside of the flames of an oil burned central heater, etc. Figure 6 is a diagrammatic view in which the moisture content (humidity) is plotted along the Y-axis and the time is plotted along the X-axis. The lowermost curve 21 shows how the air humidity decreases successively when the sauna is heated if no additional humidity is supplied. The humidity decreases from a moisture content of about 35-40% down to a moisture content of 10%, or even less. The upper several curves 22a-d show how the humidity is quickly raised in the sauna when heating the sauna in combination with using the steam generation assembly according to the invention, from a moisture content of about 35-40% to more than 45, 60, 68 and 75%, respectively, or even more depending on the number of steam coils 2a-d included in the steam generation assembly and how many steam coils are being used at the moment. The phantom line curve 23 indicates how the moisture content in a sauna can be raised in that water is simply thrown onto the sauna stones. It is evident that the increase of moisture content thereby is rather insignificant. The broken line area 24 shows the gain of moisture content that is obtained by use of the steam generation assembly according to the invention. REFERENCE NUMERALS 1 water container 13 tube 2 steam coil 14 bottom (of 3) 3 water supply chamber 15 water level 4 room 16 water level 5 steam tube 17 water level 6 return channel 18 water level 7 valve system 19 chamber 8 heater element 20 stone 9 heat distribution plate 21 lowermost curve 10 press plate 22 curve (a - d) 11 hydrometer 23 phantom line 12 control means (water level) 24 broken line area

Claims: C L A I M S 1. A steam generating assembly adapted to control the humidity in air of a room (4) to a desired level, characterized in that the steam generating assembly comprises one or more parallel steam coil slings(2) which are arranged to be mounted adjacent to a heat generating apparatus (8), and which steam coil slings (2) can, to a desired height thereof, or in a desired number, be supplied with water (I) which becomes evaporized in the steam coil or coils (2) and which, after having been evaporized is supplied (5) directly to the air of the room (4) intended to get an increased humidity. 2. A steam generating assembly according to claim 1 , characterized in that it comprises a water container (1) which is adapted to be filled with water up to a suitable level (15-18) and which is connected to the steam coil or coils (2) so that steam coil, or a desired number of steam coils are supplied with water corresponding to the water level (15-18) in the water container (1 ). 3. A steam generating assembly according to claim 2, characterized in that the water level (15-18) of the water container (1) is controlled by means of a water level controlling valve (7, 12). 4. A steam generating assembly according to claim 3, characterized in that the water level controlling valve (7, 12) is guided by an adjustable hydrometer (I I) in the room (4). 5. A steam generating assembly according to any of the preceding claims, characterized in that it is formed as a flat pack of steam coils (2) arranged for being introduced between or adjacent electric heater coils (8) or directly into the fire place of a wood burner or an oil burner. 6. A steam generating assembly according to any of the preceding claims, characterized in that the lower ends (2') of the steam coils (2) are connected to the water supply chamber (3) adjacent the bottom (14) thereof, and in that the upper ends (2") of the steam coils (2) open into a distribution chamber (3) in which drops of water or condensed water is collected and is drained (6), and from which steam leaves through an upwards extending steam tube (5) opening into the room (4) to be humidified. 7. A steam generator according to claim 6, characterized in that the distribution chamber (3) is connected to, or integral with a return channel (6) through which drops of water and condensed water is returned to the water system (3) of the assembly. 8. A steam generating assembly according to claim 5, characterized in that the steam coils (2) are covered, on one side or on each side thereof, by a heat distribution plate (9) of a well heat conducting material which can stand the heat issued by the heat generating means (8) which is arranged to provide an evaporization of the water supplied to said steam coils (2). 9. A steam generating assembly according to any of the preceding claims, characterized in that the assembly comprises two or more parallel sets of steam coil slings (2) are connected to one and the same water supply and water distribution chamber (3). 10. A steam generating assembly according to claim 8, characterized in that a press plate (10) is mounted on the exterior side of the, or each steam generation coil (2) and is arranged to press said steam coil or coils into contact with the heat distribution plate (9), and in that the entire unit comprising the heater element or elements (9), the heat distribution plates (9), the steam coils (2) and the press plates (12) are enclosed in a casing having an inner or outer insulation means.

Inventors: SALOMONSSON ULF, SALOMONSSON, ULF
Applicants: SALOMONSSON ULF, SALOMONSSON, ULF
Application year: 2001
Main classification: A61H33
IPC codes: A61H33