Abstract:
A steam heater comprising: a tube having two ends and interior walls; a heating element extending throughout the tube, wherein a passage is defined by the heating element and the tube interior walls and extends contiguously throughout the tube; a first hollow nozzle coupled to the a first end of the tube; a second hollow nozzle coupled to the second end of the tube; the first nozzle having an orifice facing the heating element; the second nozzle having an orifice facing away from the heating element, the heater having a heating capacity sufficient to convert water entering the passage via the first nozzle into steam leaving via the second nozzle.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed to improved devices for heating water. 
       BACKGROUND OF THE INVENTION 
       [0002]    WO2009047772 to the inventor describes a steam generating mechanism incorporated within a water heating system having a body, at least one heating element, on/off switch and power supply, the steam generating mechanism comprising:
   a hollow tube having a first side and a second side provided close to the at least one heating element; a one way valve connected to said first side, wherein said one way valve allows water to enter into said hollow tube; a one directional pump connected to said second side, wherein the pump is capable of discharging steam generated within said hollow tube; a pipe fluidly connected to said one directional pump wherein said pipe passes through the body for discharging said steam outwardly.   
 
         [0004]    An object of the present invention is to provide improved steam generating devices for the steam generating mechanism of WO2009047772 as well as other systems and apparatuses. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  describes a tube having a variable inner diameter and various widgets capable of impeding flow; 
           [0006]      FIG. 2  shows two tubes, one inside the other; 
           [0007]      FIG. 3A  depicts pressurized water entering a steam-heating tube in the form of drops; 
           [0008]      FIG. 3B  is a drawing of a special nozzle to provide water to the tube; 
           [0009]      FIG. 3C  depicts another special nozzle in such tube; 
           [0010]      FIG. 3D  shows a steam heating tube with special baffles to increment heating of the water; 
           [0011]      FIG. 3E  illustrates revolving baffles in the tube; 
           [0012]      FIG. 3F  shows three examples of baffles in a tube; 
           [0013]      FIG. 4  is a schematic diagram of an electrical circuit for heating water to steam in a tube; 
           [0014]      FIG. 5  is an exploded view of a percolator with a steamer; 
           [0015]      FIG. 6  is an exploded view of a kettle with a steamer, and 
           [0016]      FIG. 7  is an exploded view of a water bar with a steamer; 
           [0017]      FIG. 8  shows in perspective view vertical heating element and matching tube, and nozzles and an electrostat, and 
           [0018]      FIG. 9  shows in perspective view a horizontal heating element and matching tube, and nozzles and an electrostat. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]      FIG. 1  shows in a schematic drawing a steam heater  100  embodiment. The steam heater includes a heating block  110 , a heating element  120 , a tube  130 , nozzles and baffles, the latter will be described below. The heater  100  also includes a pump, not shown, which feeds pressurized water to the tube  130  and/or siphons steam out of the tube  130 . The heater also includes an electrical system discussed below. 
         [0020]    The steam heater may be placed under or inside the base of a kettle, in which case the block is typically heated at 1300-2300 Watts. 
         [0021]    The entrance  131  of the tube  130  is typically 3-4 mm i.d.; however, the exit  137  is typically 1-3 mm i.d., more preferably 1-2 mm. However, the tube  130  may also have a constriction  134  before an expansion  136 , all of these restrictions and expansions may serve to increase heat transfer from the tube  130  to water therein passing from the entrance  131  to the exit  137 . 
         [0022]    The water is fed to the heater  100  by a pump and/or by gravitation, the water entering the tube via at least one nozzle. One nozzle  142  has a sealed end  152 , and openings facing inner walls of the tube entrance  131 . Another nozzle  144  has an opening  154  that is as wide as the hole along the nozzle; yet another nozzle  145  has also openings facing the walls of the tube, but has less dead volume than nozzle  142 . Nozzle  146  is screw-shaped, with holes along the thread, that may help make the flow of water more turbulent and thus increase the heating rate of the water passing through. 
         [0023]    In preferred embodiments, the tube  130  includes at least one coil. 
         [0024]    In some embodiments, not shown, the steam heater includes a maze structure through which the water/steam passes; the maze may be constructed from two blocks of heating elements that match each other in grooves and ridges or one block only with a maze structure, that is sealed with a matching plate. Some embodiments may include more than one maze, for example a heating block may be sandwiched in between mazes, such that the water entering a first maze from its periphery goes to a centre point of the maze, having passed through the entire maze first, and then leaves the first maze through a passage which extends from said centre, throughout the heating block and into a centre of a second maze, the water then passing through the entire second maze before exiting as steam. Such heater may include therein the nozzles described above as well as similar nozzles, and baffles discussed below, to further facilitate heat transfer to the water passing through the maze. 
         [0025]    Another embodiment is depicted in  FIG. 2 . The heater  200  again includes a heating block  210 , a heating element (not shown), a tube  130 , nozzles and baffles. The heater  200  also includes a pump, not shown, however the pump feeds pressurized water to a first tube  202 , into whose end  203  second tube  230  is installed, so that the first tube  202  feeds the second tube  203 . In some embodiments, a valve connects first tube  202  to second tube  230 . A user may manipulate the valve or a switch operationally coupled to the valve, to select between hot water delivery from the first tube  202 , for example for delivery to the kettle or directly to a cup, and hot water delivery to the second tube  230 . In some embodiments, there is a booster pump, preferably between the valve and the second tube  230 , that may be used to boost the water pressure in the second tube  230 . In some embodiments the booster pump automatically operates whenever the switch is set to deliver water to the second tube, e.g. by the same switch that sets delivery of hot water from the first tube to the second tube; in other embodiments the booster pump can be selected to be operated independently from the valve; preferably, in such embodiments, there is a micro-switch to prevent the booster pump from operating when the valve is set to deliver hot water not to the second tube. In some embodiments, the second tube  230  is coiled around the first tube  202 . 
         [0026]    The heater also includes an electrical system discussed below. 
         [0027]      FIG. 3A  is a schematic drawing showing part of a heater  300 ′ with steam tube  330 ′. The nozzle  340 ′ is blocked at the end, and has a rim  342 ′ that extends around the nozzle to leave a narrow space between the inner walls of the tube  330 ′ and the nozzle  340 ′. Holes  344 ′ allow water to exit the nozzle  340 ′ and impinge upon the inner walls of the tube  330 ′, before passing through the narrow space. 
         [0028]    In the embodiment  300 ″ the nozzle  340 ″ is corkscrew-shaped, also blocked at end and with holes  344 ″, the corkscrew shape and the position of the holes allowing the water to become turbulent, and/or go a long and tortuous path, to facilitate heating of the water, and the water essentially impinges upon the inner walls of the tube  330 ″. 
         [0029]    In another heater  300 ′″, nozzle  340 ′″ has a very small-bore end  342 ′″, open and directed to one spot on the wall. Such spot may be locally heated more than other areas of the tube  330 ′″. 
         [0030]    Heater  300 ″″ includes in the tube  330 ″″ stationary baffles  360 ″″. The baffles  360 ″″ are preferably opposed to each other to create a narrow space through which the water passes in the tube  330 ″″. 
         [0031]    In another embodiment  300 ′″″ shown in  FIG. 3E  shows rotational baffles  370 ′″″ and/or  374 ′″″ that are installed in the tube  330 ′″″. The first baffle  370 ′″″ is prism-shaped, whereas the second baffle  374 ′″″ is wheel-shaped. Preferably, the baffles have ridges on surfaces thereof, to facilitate interaction with water passing by the baffles, to further heat the water. Preferably, the baffles are installed in a maze-shaped heating block rather than in a tube, in regard of ease of construction. 
         [0032]    As shown in  FIG. 3F , three types of stationary baffles  362 ″″″,  364 ″″″,  366 ″″″ are shown. According to the requirements such as energy expenditure efficiency, heater size requirements and restrictions, steam temperature and delivery rate, one or more baffle may be selected. 
         [0033]      FIG. 4  shows an electrical setup  480  suitable for use in a steam heater embodiment  400 . The electrical setup  480  includes the heating element  420 , switches  481 , a pump  482 , indicating lamps  483 , a PCB  484 , at least one thermostat  485 , power supply  486 . 
         [0034]    Preferably, the electrical setups are set to bring the steam to a certain temperature, in order to optimize the steam for its designated purpose, e.g. to prepare milk froth for coffee. The steam heaters may be incorporated in an electric kettle, or a percolator, or a milk frother, or a water bar such as Tami 4® etc. 
         [0035]      FIG. 5  shows in an exploded view a modified percolator  1000 . The percolator has the known container  10 , a heater  11  in contact with a steam pipe  12 , lid  13 , filter holder  14  and coffee receptacle  15  that sits on a holding plate  16 . The steamer  1400  comprises a junction  1492 , leading from pipe  12  to pump  1482 , which when operated provides water to the maze  1130  via a nozzle such as one of nozzles  1142 - 1146 . 
         [0036]      FIG. 6  depicts a modified kettle  2000 . The kettle  2000  includes a body  17  that is shown in cutout view. A cold-water container  2195  (also shown in cutout view) is situated inside the body  17  that is thermally insulated from the space inside the body  17  and outside the container  2195  such that the water therein is less than 50° C. The kettle has a plate  2196  that in commercially available kettles holds a heating element and seals the bottom of the body  17 . However, in contrast to the commercially available plates, plate  2196  has an aperture which allows to fluidly connect the container  2195  with the steamer pump  2482 . Water goes from the pump  2482  to the maze  2130 . The maze may fit into a bottom plate  2197 . 
         [0037]      FIG. 7  shows a modified water bar  3000  in which water can be provided for steaming from mains via an electric or manual (or magnetic etc) valve to maze  1130 , or from a reservoir  2484  via a pump  2482  to the maze  1130 . 
         [0038]      FIG. 8  shows in perspective view a vertical heating element  520  and matching tube  530 , and nozzles  545   a  and  545   b  and an electrostat  590 . The element  520  is vertical in respect to a kettle base (not shown). Water enters via the bottom nozzle  545   a,  which has an opening (not shown) that faces the heating element  520 , i.e. in this particular case the nozzle does have an opening at the end, as the water generally flows in the tube  530  in a different direction. The opening  555   b  of the top nozzle  545   b,  from which the steam exits, preferably faces upwards, which is not strictly opposite the direction of the heating element (vertical) but for practical purposes faces away from the heating element. The nozzles  545   a  and  545   b  may have threads  546  that match threads (not shown) on branches  534   a  and  534   b  on the tube  530 , so as to allow firmly screwing the nozzles  545   a,    545   b  to the tube  530 , yet allowing easy removal of the nozzles  545   a,    545   b  for cleaning the tube from dirt, scaling from precipitates etc. 
         [0039]      FIG. 9  shows in perspective view a horizontal heating element  620  and matching tube  630 , and nozzles  645   a  and  645   b.    
         [0040]    The exit nozzles  545   b  and  645   b  both have openings  555   b  and  655   b  facing upwards, such orientation may help prevent release of liquid from the heater since the liquid may be located mainly at lower parts of the tube  530 ,  630 . 
         [0041]    The steam heater with the tubes in horizontal orientation ( 630 ) has in preferred kettle embodiments a hollow base (under the body wherein water is normally heated). The heating element and tube is situated inside the base, such that the only access a user has is to a switch operationally coupled to the heater, to allow turning on the steam providing mode. In experiments with such embodiments, wherein the tube  630  was about 250 mm long and had an internal height of 8 mm (between the heating element  520  and the roof of the tube  530  on the inside, the width of the tube typically being somewhat narrower), tap water at about 25° C. was fed by a pump, at a flow rate corresponding to a pressure of about 5 bar. A sufficient amount of steam was produced within 10-20, enough to satisfactorily cream a cup of coffee. 
         [0042]    Typically, the heating element  520 ,  620  has a power of 600-900 W to provide a desirable amount of steam in this embodiment. 
         [0043]    While preferred embodiments have been described, the invention is only limited by the scope of the claims. 
         [0044]    Those skilled in the art will recognize that the method and system of the present invention has many applications, may be implemented in many manners and, as such, is not to be limited by the preceding and following exemplary embodiments and examples. Additionally, the functionality of the components of the preceding and following embodiments may be implemented in different manners. Further, it is to be understood that the steps in the embodiments may be performed in any suitable order, combined into fewer steps or divided into more steps. Thus, the scope of the present invention covers conventionally known and future developed variations and modifications to the system components described herein, as would be understood by those skilled in the art.