WO2013025208A1

WO2013025208A1 - Steam generator system

Info

Publication number: WO2013025208A1
Application number: PCT/US2011/048007
Authority: WO
Inventors: Michael George COLBURN; Stephen James BOGNER
Original assignee: Wood Stone Ideas Llc
Priority date: 2011-08-16
Filing date: 2011-08-16
Publication date: 2013-02-21
Also published as: RU2014109828A; HK1199297A1; RU2584627C2; CN103857958B; AU2011374994A1; EP2745050A4; MX2014001813A; JP2014526028A; AU2011374994B2; MX353543B; CN103857958A; JP6065237B2; KR20140064862A; EP2745050A1; CA2844489A1

Abstract

A system for generating steam from an electrolytic solution includes a steam generating tank, a flow producing device, an electric current measuring device, and a controller. The steam generating tank includes a first electrode and a second electrode. The first electrode and the second electrode are arranged to contact the electrolytic solution when the electrolytic solution is provided in the steam generating tank. Electrical current flows between the first electrode and the second electrode through the electrolytic solution. The electrical current heats the electrolytic solution to produce the steam. The controller is connected to the flow producing device to to turn on and turn off provision of the electrolytic solution to said steam generating tank based on the electrical current measured by the electric current measuring device.

Description

STEAM GENERATOR SYSTEM

Field

This patent application generally relates to a steam generator system. More specifically it relates to a system for generating steam by passing a current through water. Even more specifically it relates to a system for delivering a predetermined amount of steam, intermittent amounts of steam or a continuous amount of steam.

Background

In steam use applications the need for rapid generation and replacement of steam is often required for speed of the work being performed by the steam. Different work to be performed by steam can require a determined amount of steam, intermittent amounts of steam or a continuous amount of steam. Food cooking is one such application where it is necessary to provide a continuous amount of steam to rapidly cook or reheat bulk food in the quantities needed for serving large numbers of people, such as in a restaurant or for banquet feeding. In other applications where portions of food are to be reheated for individual servings such as sandwich meats, short blasts of steam in small amount, repeated at intervals are preferable. Where a single function is to be performed for a specific amount of time a determined amount of steam is often preferable.

In steam generation by an electrical resistance element, electrical energy must first heat an electrical resistance element then its casement and then the water to be used to produce steam. An electrical resistance element is generally enchased in a sheath of metal or other material which is heated by the resistance element when the element is submerged in water to generate steam. A delay in heating the water to sufficient temperature to generate steam occurs due to the conduction of heat through layers of material and then into the water molecules.

In attempts to speed steam generation, electrical elements are often oversized and overpowered in order to quickly heat the sheathing so that the sheathing can then heat the water, which generally causes excessive energy use. When steam is required in a device with electrical resistance elements, full power is applied to the element, in this way the surface temperatures of the element and its sheathing become much hotter than the water and heat transfer is faster. When steam is no longer needed, energy is removed from the resistance element, however heat in the resistance element and casement continues to transfer to the water and is wasted. In this way more energy is used than would be necessary if a direct application of energy to heat was provided in just the amount of energy needed to supply the amount of steam necessary to perform the work required. Other problems are created by heating the element and sheathing to a temperature much hotter than the water to be heated. Dissolved solids such as calcium carbonate and magnesium are percolated out of the water and these particles adhere to the surface of the element sheathing, thus forming a layer of deposits called lime scale on the heat transfer surface. These lime scale deposits become another layer of heat transfer and reduce the speed of heat transfer further. The lime scale then causes more energy use for the work required. Lime scale is also a major factor creating maintenance and service requirements for steam generation devices.

In continuous steaming applications, steam generators having storage for a quantity of water are used. The size of the reservoir for water storage is based on the maximum amount of steam generation required in a period of time. The generating of steam then requires heating this entire mass of stored water to near steam generation temperatures in order to provide the required amount of steam as quickly as possible. Heating this entire quantity of water is required in continuous steaming applications to offset the amount of time required to take water to steam in a continuous supply using electrical resistance elements. Energy is wasted by heating the entire supply of stored water. After water in the heated reservoir is heated to generate steam, new water is supplied to the water storage cooling the entire amount of water. When new water is added the temperature of the entire quantity of water is reduced and must be reheated to the desired maintenance temperature, again wasting energy.

Attempts to speed the generation of steam in a steam generator with water storage have included the use of a pressurized housing in which the water can be heated and maintained at a higher temperature so that its release to steam use will flash the water from superheated water to steam. Devices with steam generation and pressurized water are generally complex, heavy due to the weight of components and due to the stored supply of water and are prone to service and maintenance issues. A great deal of energy is expended to reheat and maintain the water supply at a temperature ready to produce steam. In an alternate steam generating method serving the need for rapid steam generation devices, a nozzle supplies a small amount of water as a spray against a hot surface where it flashes to steam. In this way a small quantity of steam is produced almost instantly and then is used for the application intended. Additional quantities of water are sprayed against the hot surface intermittently to provide additional quantities of steam for the intended purpose. The hot surface is heated by an encased electrical element or in some cases water is sprayed directly on an electrical element encased in sheathing. This method of steam generation provides an intermittent amount of steam but not a continuous amount of steam. In this solution the amount of steam that can be created at one time is limited first by the quantity of water contained in each spray and then by the surface temperature of the surface on which the water is sprayed. Repeated sprays can create additional steam but sprays must be delayed until the heated surface has had a chance to recover adequate temperature to flash more water to steam, limiting the amount of steam that can be generated. In some cases the electrical element provided to heat a surface or provided as a flashing surface is increased in size to allow for faster recovery in order to flash more water to steam in a given time, wasting energy.

In instances where the need for steam is often unpredictable, the heated surface is maintained in a hot surface condition in order to be ready for steam production when required, this also wastes energy. In this solution, the dissolved solids of the water supply are given up to the heated surface when the water is flashed to steam. The dissolved solids form a lime scale coating on the flashing surface causing it to become less efficient at heat transfer. This results in the need for additional energy to heat the surface and additional time to reach a temperature capable of generating steam. These conditions result in a reduction in the amount of steam that can be generated and the speed at which steam can be generated. The buildup of lime on the surface eventually leads to the need for maintenance or repair. Because of the inherent problems with the related art, there is a need for a new and improved steam generator system for rapidly creating steam by a direct conversion of electrical energy to heat in the water molecules and in controlled sequences to deliver a determinant amount of steam, intermittent amounts of steam or a continuous amount of steam.

Summary

One aspect of the present patent application is a system for generating steam from an electrolytic solution. The system includes a steam generating tank, a flow producing device, an electric current measuring device, and a controller. The steam generating tank includes a first electrode and a second electrode. The first electrode and the second electrode are arranged to contact the electrolytic solution when the electrolytic solution is provided in the steam generating tank. Electrical current flows between the first electrode and the second electrode through the electrolytic solution. The electrical current heats the electrolytic solution to produce the steam. The controller is connected to the flow producing device to to turn on and turn off provision of the electrolytic solution to said steam generating tank based on the electrical current measured by the electric current measuring device. Another aspect of the present patent application is a system for generating steam from an electrolytic solution. The system includes a steam generating tank. The steam generating tank includes a first electrode and a second electrode. The first electrode and the second electrode are arranged to contact the electrolytic solution when the electrolytic solution is provided to the steam generating tank and when the first and the second electrodes are connected to a source of AC electrical power. Electrical current flows between the first electrode and the second electrode through the electrolytic solution. The electrical current heats the electrolytic solution to produce the steam. Flow of electrical current automatically stops when all electrolytic solution in the steam generating tank has been converted to steam.

Brief Description of Drawings

The foregoing and other aspects and advantages of the invention will be apparent from the following detailed description as illustrated in the accompanying drawings, in which:

FIG. 1 is an block diagram of one embodiment of a steam generator system;

FIG. 2 is a block diagram that includes one embodiment of a control circuit for controlling the steam generator system of FIG. 1; FIG. 3 is a three dimensional view of one embodiment of a steam generating tank;

FIG. 4 is a cross sectional view of the steam generating tank of FIG. 3; FIG. 5 is a three dimensional view of another embodiment of a steam generating tank;

FIG. 6 is a cross sectional view of the steam generating tank of FIG. 5;

FIG. 7 is a three dimensional view of one embodiment of a filter;

FIG. 8 is a three dimensional exploded view of another embodiment of a steam generating tank and its electrical and mechanical connectors; and

FIG. 9 is a three dimensional view of one embodiment of a steam generating system.

Detailed Description

One embodiment of the present patent application provides a system for rapidly creating steam. Electrical current passing through an electrolytic solution of water heats the electrolytic solution to the boiling point to deliver a pre-determined amount of steam, intermittent amounts of steam or a continuous amount of steam. The electrolytic solution has an ionic content sufficient for a high current to flow to provide rapid ohmic heating. The electrolytic solution is received in a steam generating tank where it contacts electrodes. A control system directs production of steam in a continuous, intermittent, or a pre-determined amount. In one embodiment a water reservoir supplies the electrolytic solution for conversion to steam in the steam generating tank. In one embodiment, a pump is used to flow the electrolytic solution from the reservoir to the steam generating tank.

The current flowing between electrodes in the steam generating tank is controlled by the combination of ionic content added to the water, the level of the electrolytic solution in the steam generating tank, and operation of a phase angle controller and a current sensor of an electrical circuit.

In one embodiment, the ionic content of the water is adjusted before use in steam generation. In another embodiment tap water with its inherent conductive impurities is used for the steam generation.

In one embodiment, energy is provided to operate the steam generating system only when the steam is required by an apparatus that uses the steam. Energy for maintaining steam or heated water can be avoided. In one embodiment steam generation is controlled by the resupply of a quantity of electrolytic solution to the steam generating tank. One embodiment of the present patent application can produce a fixed quantity of steam determined by a quantity of electrolytic solution provided to the steam generating tank and in contact with the electrodes in the steam generating tank until that quantity is completely converted into steam. The system can also be operated to provide a small quantity of steam intermittently. The system can also be operated to provide a continuous quantity of steam by continuous supply of electrolytic solution.

The present applicants found that energy conversion was at a high efficiency. They also found that the system consumes energy only when water is present in the steam generating tank and that it automatically turns off when all of the electrolytic solution has been converted to steam because the circuit is thereby interrupted. They also found that steaming stops quickly when current supply to the electrodes was switched off. As no surfaces get hotter than the electrolytic solution in the steam generating tank and the steam generated in the tank, lime scale is avoided, thus avoiding regular maintenance or repair. In this configuration, the present applicants found that precipitating salt and solids are found along with steam condensate that flows into a collection pan in the compartment using the steam. In other configurations salt and solids can be flushed out of the steam generating tank with a plain water or chemical rinse.

In one embodiment, the steam is generated for a cooking appliance. One embodiment is light weight and requires very few connections for use and can be attached to a particular appliance when steam is required. Several of the embodiments are in a steam ready condition without the consumption of electricity until steam is called for.

In steam generator system 10 electrolytic solution 11 is received by steam generating tank 17 for producing steam in a continuous, intermittent, or a pre-determined amount, as determined by control system 16, as shown in FIG. 1. The steam is rapidly created via direct conversion of electrical energy to heat in the electrolytic solution that is to become steam. Steam generating system 10 also includes reservoir 13, filter 12, pump 14, and check valve 15.

In one embodiment, pump 14 is replaced with another type of flow controlling device. In one such embodiment flow of electrolytic solution 11 into steam generating tank 17 is by gravity feed and the flow controlling device is an electrically controlled valve. In this embodiment controller 21 that would otherwise turn pump 14 on and off would instead open and close the valve to inject electrolytic solution from reservoir 13 into steam generating tank 17. While in the remainder of the description in this patent application the flow controlling device is called pump 14, it is understood that the gravity feed and valve scheme or another such scheme may equally well be used.

In the embodiment of FIG. 1 reservoir 13 holds a supply of electrolytic solution 11. In an alternate embodiment, a connection for supply of electrolytic solution 11 could be provided for a continuous supply in place of or in addition to reservoir 13. Reservoir 13 can be fabricated of a blow molded or injection molded plastic or can be of another material suitable for the storage of an electrolytic solution of water.

Electrolytic solution 11 is adjusted in ionic content by passing water through filter 12. Filter 12 is so constructed as to direct water flow through a series of holes and through an ionic material that adds ionic content to the water as it passes through the filter 12. Applicant made filter 12 by loading table salt into a cheesecloth bag and inserting the bag into a filter housing. To remove chlorine and other impurities from the water applicant loaded charcoal into another cheesecloth bag and inserted that bag into the filter housing as well. As water runs thorough filter 12 toward reservoir 13, the flow of water is controlled by the hole size in the filter housing. The hole size is set to allow adequate residence time for the water with the salt so that the desired dissolved ionic content is achieved for electrolytic solution 11 that flows out through the filter's discharge holes into reservoir 13.

In another embodiment, applicants simply added salt to the reservoir and then filled the reservoir with water, thereby achieving sufficient residence time for the salt to dissolve and achieving the desired concentration of about a quarter teaspoon of salt per gallon for the reservoir which held about 2 gallons of electrolytic solution 11.

By either technique, electrolytic solution 11 is adjusted in ionic content by the addition of an amount of sodium chloride in an approximate ratio of approximately 3/4 of a gram per gallon of water. Addition of an ionic material to water is described in commonly assigned US patent publication 2010/0040352 "Rapid Liquid Heating," incorporated herein by reference. The ionic content may include one or more potable ionic elements, such as sodium chloride. A charcoal filtering element can be included to remove chlorine and other impurities from the water entering steam generating system 10. The amount of sodium chloride and the amount of dissolved solids dissolved in electrolytic solution 11 will determine the conductivity of electrolytic solution 11, the current flow in electrolytic solution 11, and the rate of heating and steam generation by electrolytic solution 11.

Reservoir 13 is connected to pump 14 which in turn is connected to one way check valve 15 connected to steam generating tank 17, as shown in FIG. 1. Pump 14 is controlled by on and off signals received from control system 16. The longer control system 16 has pump 14 turned on the more water is pumped to the interior of steam generating tank 17 and the higher the level of water in contact with electrodes in steam generating tank 17. Check valve 15 allows flow to steam generating tank 17 but prevents steam generated in steam generating tank 17 from flowing back to pump 14. The output of steam generating tank 17 is directed to steam chamber 19, such as a cooking appliance, compartment, or other device that uses steam. The connections between components that permit water and steam flow may include piping, tubing, or other suitable structural components. Also illustrated connected to steam generating tank 17 in FIG. 1 are connection boxes for receiving a positive AC power line and a neutral AC power line for connection to electrodes in steam generating tank 17.

FIG. 2 illustrates one embodiment of electrical circuit 20 used with the embodiment of FIG. 1. Electrical circuit 20 controls operation of pump 14 and monitors and controls current flow between electrodes in steam generating tank 17. In one embodiment, current is controlled to avoid exceeding a current load set point. A circuit breaker is also included which would disrupt current flow if current exceeds its preset disconnect value. In one embodiment, current is maintained relatively high, close to but not exceeding the circuit breaker preset disconnect value current limit in order to most quickly generate the desired amount of steam without interruption. The amount of dissolved solids and sodium chloride in the water could easily reach a level where a current load limit could be achieved and exceeded if other controls were not in place.

In one embodiment, electrical circuit 20 is connected to plug 26, such as a 120V, 20A NEMA 5-20P for plugging into a wall outlet. However, it is appreciated that other power supplies may be used, such as 208, 220, 240, and 440 volts. As also illustrated in FIG. 2, current sensor 22, such as sold by Digi-key Corporation, South Thief River Falls, Minnesota, is located on controller 21, wherein current sensor 22 reads the level of current being provided to steam generating tank 17 and is programmed to supply current to pump 14 based on the current level programmed into controller 21. Interface to controller 21 allows operator to put in time for operation. Start and stop control is also provided. For a 120 volt system, for example, the breaker current is 20A and the maximum operating current would be factory set at 15amps. Similarly, for the higher voltage systems a corresponding circuit breaker and a maximum operating current are provided.

In one embodiment, when current sensor 22 senses that current flow to electrodes in steam generator tank 17 has dropped below a set point for normal operation, such as 14 amperes, controller 21 activates pump 14. Pump 14 then supplies electrolytic solution 11 to steam generating tank 17, which raises the level of electrolytic solution 11 in steam generating tank 17 which increases the area of submerged electrodes, lowers resistance, and increases the electrical current flowing between electrodes in steam generating tank 17. When the electrical current flowing across gap 37 between the electrodes rises to a preset level as determined by current sensor 22, controller interrupts the power to pump 14, turning off the flow of electrolytic solution 11 to steam generating tank 17 and halting the rise in electrical current.

In this embodiment, since controller 21 is preset so steam generating tank operates with a specified level of current flow between electrodes to maximize rate of steam generation, current sensor 22 and pump 14 work together to adjust and maintain a level of current near the maximum set point, such as 14 amperes for a 20 ampere system. This scheme allows for variation in ionic content of the electrolytic solution, such as over ionization of the water, by adjusting the water level in contact with the electrodes in steam generating tank 17 to maintain the pre-set level of current flow and steam generation. Adjusting level of electrolytic solution 11 in steam generating tank 17 allows resistance of electrolytic solution 11 to remain constant even if resistivity of electrolytic solution 11 varies. When current falls below a preset level, say 14 amperes, controller 21 turns pump 14 on and when the current goes back up to the 14 ampere level controller 21 turns pump 14 off. Thus, level of electrolytic solution 11 in steam generating tank 17 is adjusted to achieve the preset current even if concentration of electrolyte varies. In one embodiment, pump 14 turns on and off several times per minute. In one embodiment, controller 21 provides that current sensor 22 checks current flow every 3 seconds and if current is measured below the 14 ampere set point, controller 21 turns on pump 14 and keeps pump 14 on until current reaches the 14 ampere set point. When pump 14 is running, current sensor 22 monitors current continuously so controller 21 can turn pump 14 off at any time. Although in this example, current sensor checks current every 3 seconds, the interval for checking current and the current set point can be set to other values.

As illustrated in FIG. 2, current sensor 22 is also wired into phase angle controller 24, such as the SSRMAN-1P Microprocessor Controlled SSR Mounted Phase Angle Control Module, available from NuWave Technologies, Inc., Norristown, Pennsylvania. The supplied power is one of the potential variables in determining the current flow. Phase angle controller 24 operates to prevent RMS current from exceeding a preset value. Control over the conductance of entering electrolytic solution 11 and control over the level of electrolytic solution 11 in steam generating tank 17 allows maintenance of a high working current. However, at such a peak current level, small variations can cause an overshoot of a breaker set point and cause the breaker to open and an electrical disconnect which would stop production of steam.

Alternatively, an operator may add far too much electrolyte, increasing conductivity to the point that the line voltage would allow current to exceed the breaker set point. Phase angle controller 24 in conjunction with the current sensor 22 recognizes that RMS current is approaching the set point and limits the current by switching off current flow for part of each AC cycle. Thus, the high current flow is maintained but not exceeding the set point limit. Operation of current sensor 22 and phase angle controller 24 to adjust RMS current, along with control over ionic content of electrolytic solution 11 provides a high level of current near current maximum without overshooting the maximum current limit.

In one embodiment of use of the steam generating system, by controlling the quantity and frequency of flow of electrolytic solution 11 to steam generating tank 17, steam generating system 10 can generate a continuous supply of steam. In this embodiment, controller 21 pumps electrolytic solution 11 at a frequency sufficient to maintain a constant quantity of water in steam generating tank 17 as steam is generated. In another embodiment, electrolytic solution 11 may be added at intervals of time, such as every ninety seconds, to provide an intermittent supply of steam. In another embodiment, a specific amount of steam is generated by supplying an amount of water to steam generating tank 17, such as one tenth liter of electrolytic solution 11, and steam is generated until this amount of electrolytic solution 11 is fully depleted without resupply. When electrolytic solution 11 is supplied to steam generating tank 17, water will seek a common level between the electrodes. Current will only flow between positive and neutral electrodes when a connection between the electrodes is made by electrolytic solution 11 being present. In this way steam generation ceases when either all electrolytic solution 11 is evaporated to steam and no additional water is provided or when electrical power to the electrodes is switched off or otherwise removed.

In one embodiment, power is not supplied to maintain electrolytic solution 11 hot in order to save energy. This embodiment takes advantage of the fact that only a small amount of electrolytic solution 11 may be needed to supply the desired amount of steam at any instant, and converting a small amount of electrolytic solution 11 to steam in steam generator tank 17 is very fast. For example, a few milliliters of electrolytic solution may be added to steam generator tank 17. Applicants found that such a small volume of room temperature water was converted to steam by the steam generator system within 3 seconds. Speed is enhanced because the steam generator system of the present application provides a very large amount of electrical power passing through a relatively small amount of electrolytic solution. For example, with a 120 volt supply providing 14 amperes of RMS current, 1680 watts are supplied, which provides 5040 joules of energy in 3 seconds. This is enough energy to raise the temperature and boil away 8ml of water from 20 C in those 3 seconds. As steam generator tank 17 can be continuously replenished with electrolytic solution 11, steam generator tank 17 can then supply steam continuously with no further delay.

As steam is generated between electrodes of steam generator tank 17, the steam bubbles up into a steam chamber in steam generator tank 17 or to an appliance that uses the steam. In one embodiment, no steam valve is provided since the supply of steam is determined by the amount of electrolytic solution provided to steam generator tank 17 and by operation of control system 16.

FIGS. 3 and 4 illustrate one embodiment of steam generator tank 30 which receives electrolytic solution 48 and outputs steam 49. Steam generator tank 30 includes shell 31 comprised of a metallic material, such as titanium or another conductive and non-corrosive material, such as graphite. In one embodiment, shell 31 is cylindrical in shape and connected to neutral line 43 of electrical circuit 20. Shell 31 is fitted with first end cap 32 and second end cap 33, preferably each constructed of a non-conductive material, such as polypropylene, to form a water-tight, sealed interior space. In one embodiment, shell 31 is also the outside surface of steam generator tank 30.

In this embodiment, first end cap 32 is fitted with input fitting 38 for receiving electrolytic solution 48. First end cap 32 also has output fitting 39 for outputting steam 49 for delivery for its purpose, such as heating food. Input fitting 38 and output fitting 39 may be fabricated of a tubular, barbed structure which is adapted to receive and fiuidly connect to a hose, pipe or other transferring medium with a tube clamp or other fitting device.

In this embodiment, second end cap 33 is also fitted with an electrical fitting 41 for receiving positive power line 42 of electrical circuit 20. Positive power line 42 extends within channel 34 along the bottom surface of second end cap 33 that is not connected to the fluid filled interior space. Alternatively, positive power line 42 can extend within an opening within second end cap 33. Electrical fitting 41 may include a screw which permits transfer of the electrical connection to positive electrode 40 within the interior space of steam generator tank 30. End cap 33 also includes cover 45, formed of a non-conductive material, such as polycarbonate, installed over the electrical connection of electrical fitting 41 and positive power line 42. Positive electrode 40 is in electrical connection with electrical fitting 41 and located within the interior space of steam generator tank 30. Positive electrode 40 is sealed along a lower end with

O-shaped, silicone seal ring 46. In one embodiment, positive electrode 40 is fabricated of a graphite material. Alternatively, other conductive materials may be used, such as stainless steel, titanium. In one embodiment both electrodes 31, 40 were fabricated of a graphite material. Gap 37 between the outer circumference of positive electrode 40 and the inner circumference of conductive shell 31 holds electrolytic solution 48 for current flow there between.

The interior space of steam generator tank 30 includes a lower space that has positive electrode 40, gap 37, and a portion of shell 31 , and an upper space which serves as expansion chamber 36, as shown in FIG. 4. In one embodiment of operation of steam generator tank 30, electrolytic solution 48 is fed to the interior space of steam generator tank 30 in gap 37 between positive electrode 40 and conductive shell 31. The height of electrolytic solution 48 in this filled gap is adjustable and may vary during operation, as described herein above. With electrolytic solution 48 in gap 37 and in electrical contact with positive electrode 40 and conductive shell 31, current flows between electrodes 31, 40, creating heat that boils electrolytic solution 48 to create steam 49.

The space above positive electrode 40 in the interior space of steam generator tank 30 serves as expansion chamber 36 for electrolytic solution 48 vaporizing to steam 49, which due to the confinement creates pressure which forces steam 49 to exit from outlet 39 and enter chamber 19 or another receptacle where the steam is intended to go. Expansion chamber 36 has a volume sufficient to provide enough steam 49 to maintain a continuous supply of steam 49 if desired. Alternatively, an intermittent or a specified amount of steam can be provided.

The variables to steam generation are the size of gap 37 between the conductive shell 31 and positive conductive electrode 40, the height or level of electrolytic solution 48 in gap 37, the conductance and resistance of the electrolytic solution 48 in gap 37, and the applied electrical voltage. In one embodiment, adjusting the level of electrolytic solution 48 in contact with positive electrode 40 and conductive shell 31 is one method of adjusting and controlling the current flow and the rate of steam generation. In another embodiment, a current sensor is used to sense the current, and when the current falls below a set point, such as 14 amperes, controller 21 turns pump 14 on, driving additional electrolytic solution to flow into gap 37 of steam generator tank 17. Electrolytic solution 11 continues to flow until current sensor 22 measures that current has increased to the set point, 14 amperes. At that point, controller 21 turns off pump 14. In one embodiment, once pump 14 turns off no measurement of current is taken by current sensor until a designated time, such as 3 seconds, has passed. In this embodiment, pump 14 can at most turn on every 3 seconds. In one embodiment, gap 37 between positive electrode 40 and conductive shell 31 is 1/4 inch, the height of positive electrode 40 is about 1/3 of the height of the interior space in steam generator tank 30 and the total height of this interior space is approximately 5 inches. However, it is appreciated that various alternate embodiments, shapes, and sizes may be used.

FIGS. 5 and 6 illustrate another embodiment of steam generator tank 50. Steam generator tank 50 includes housing 51 constructed of a non-electrically conductive material, such as polypropylene. It may be fabricated of any material that will not convey electrical current or of a material, such as a metal, that is coated with a non-conductive material, for example, steel coated with PTFE. Housing 51 includes sidewalls 52 and bottom 53 to form a rectangular, box-shape and a rectangular interior space. Other shapes may be used. Housing 51 has an open top that is closed with steam housing cover 55 and sealed with gasket 56. Steam housing cover 55 is secured by fasteners 57 to seal housing 51 shut in a water-tight manner. Housing 51 includes inlet tube 65 and steam supply discharge tube 66. Housing 51 generally includes first electrode 60 and second electrode 61. Housing 51 may also include third electrode 62. Housing 51 can also include fourth electrode 63. Electrodes 60-63 are fabricated of a corrosion-resistant electrically conductive material, such as stainless steel, titanium or a graphite material. In one embodiment, electrodes 60-63 are evenly-spaced and are rectangular, plate-shaped. Third electrode 62 and fourth electrode 63 may be electrically connected to electrodes 60 and 61. In one embodiment, first electrode 60 and third electrode 62 are connected to one leg (i.e. positive) of power and second electrode 61 and fourth electrode 63 are connected to the second leg (i.e. negative or neutral) of power of the power supply, for example, 120 volts.

The specific shapes and sizes of electrodes can vary to match the size and shape of steam housing 51 while configured to allow electrolytic solution to contact all electrodes 60-63. In one embodiment notch 64 is provided to allow liquid flow between electrodes 60-63, wherein the notch 64 would generally be located along a bottom edge of the electrodes 61, 62. Space between electrodes may be adjusted to facilitate flow of current through electrolytic solution 11 in an efficient manner. In this embodiment, electrical current is provided by power cord and plug 69 similar to other embodiments. Alternately a hard wired connecter may be used. Electrical connection box 68 is provided adjacent to housing 51 to receive electrical wires 67 for reciting control commands from control system 16 and to provide connection from power cord and plug 69 to electrodes 60-63.

Filter 70 includes base housing 71 and water filter cap 74 to seal base housing 71 after containers 72, 73 of filter material are inserted, as shown in FIG. 7. The filter material is packaged in individual replaceable containers 72, 73, such as the cheesecloth bags of table salt and charcoal described herein above. One embodiment includes at least one replaceable container 72 of ionic material, such as table salt and one replaceable container 73 of an alternate filter material, such as charcoal or carbon. Filter cap 74 includes communication holes 75 that control the flow of inlet water and outlet electrolytic solution through filter 70. FIG. 8 illustrates another embodiment of steam generator tank 80 and its connectors that can be used for providing steam to an appliance requiring steam, such as a clothing steamer. Steam generator tank 80 includes housing 81 fabricated of a heat resistant plastic, such as polypropylene. In one embodiment, housing 81 is formed of a clear or a semi-transparent heat resistant material. Housing 81 can take different shapes, such as the tube shape of FIG. 8. In one embodiment, steam generator tank 80 has sealable end caps 82, 85 that attach by means of threads on each end of housing 81 and on removable caps 82, 85. Disposed within housing 81 are first removable electrode 90 and second removable electrode 91. First removable electrode 90 and second removable electrode 91 are fabricated of a conductive material, such as graphite and are positioned to electrolytic solution to contact each electrode 90, 91 equally when the housing 81 is positioned in an upright position, as shown in FIG. 8.

First end cap 82 includes electrode recesses and communications port 83 for steam to exit and for the connection to steam supply line 92. Communications port 83 may have a barb fitting. In one embodiment, first end cap 82 has an internal O-shaped ring gasket to seal against steam or water leakage. Mounted to second end cap 85 is electrode mount 86 internal to and electrically separate from second end cap 85. Electrode mount plate 86 includes mount caps 87 for receiving the ends of pencil-shaped electrodes 90, 91 and for providing electrical contact to electrodes 90, 91. Second end cap 85 includes a gasket that provides a steam- and water-tight seal when end cap 85 is threaded to housing 81. Electrode mount plate 86 and mount caps 87 stay stationary as second end cap 85 is rotated to complete a screw tight seal.

As illustrated in FIG. 8, one embodiment of electrical supply line 95 includes a two-piece structure. First connector 97 has a male component and a second connector 98 a female component to detach steam generating tank 80 from electrical plug 99. Electrical plug 99 extends from the wall outlet to second connector 98. When second connector 98 is connected to first connector 97 electrical current can flow to electrodes 90, 91 through the electrical connection within the mounting caps 87. Water within housing 81 then boils to steam which is transferred to the appliance through supply line 92. In one embodiment, supply line 92 is connected to an appliance through quick connect coupling 93. Additional electrodes may be included within housing 81. First and second connectors 97, 98 may include a safety lock for preventing accidental disengagement. They may also include nonconductive shielding. In one embodiment for its use, no control system is provided for the embodiment of FIG. 8. An operator may put in table salt and fill housing 81 with tap water to a fill line at a sink. Then the operator can plug the steam generating system into a wall outlet and let it produce steam and run until all the water is used up. In many places the system would operate with tap water and generate steam even without the addition of table salt because of dissolved solids in the ordinary tap water.

FIG. 9 illustrates another embodiment of steam generator system 10 of the present patent application as it may be sold to consumers for cooking or other activities requiring constant, intermittent, or a pre-determined supply of steam.

Reservoir 100 of steam generator system 10 of FIG. 9 is fabricated of a clear, removable and washable material, such as plastic, and is removable from control box 101. Control box 101 includes a steam generator tank, such as steam generator tank 30 shown in FIGS. 3, 4. Such a steam generator tank 30 inside control box 101 stands upright and is fed by reservoir 100.

Control box 101 also includes the circuitry of control system 16 as illustrated in FIG. 2. Control box 101 may also include on/off indicator 102 and various other indicators, an on/off switch, and a knob for setting time of operation that is connected to controller 21. Steam generator system 10 also includes condensate catch pan 103 which is removable from under steam receiving compartment 104. Steam from steam generating tank steam in control box 101 passes into receiving compartment 104 and into steam chamber 107 that may receive various food or non-food items therein. Steam receiving compartment 104 and steam chamber 107 include hinged cover 105 with handle 106. In this embodiment, steam chamber 107 includes a plurality of openings 108 along one or more surfaces allowing steam from steam receiving compartment 104 to travel through into steam chamber 107. Condensate from the steam drops down into condensate catch pan 103.

While the disclosed methods and systems have been shown and described in connection with illustrated embodiments, various changes may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

A system for generating steam from an electrolytic solution, comprising a steam generating tank, a flow producing device, an electric current measuring device, and a controller, wherein said steam generating tank includes a first electrode and a second electrode, wherein said first electrode and said second electrode are arranged to contact the electrolytic solution when the electrolytic solution is provided to said steam generating tank, wherein electrical current flows between said first electrode and said second electrode through the electrolytic solution and wherein said electrical current heats the electrolytic solution to produce the steam, and wherein said controller is connected to the flow producing device to turn on and turn off provision of the electrolytic solution to said steam generating tank based on the electrical current measured by the electric current measuring device.

The system as recited in claim 1, wherein said flow producing device includes a pump.

The system as recited in claim 1 , further comprising a reservoir, wherein said reservoir is for storing the electrolytic solution, wherein said flow producing device is connected for delivering the electrolytic solution from the reservoir to said heating tank.

The system as recited in claim 1 , further comprising a device for supplying ionic content to water to provide said electrolytic solution.

The system as recited in claim 4, wherein said device for supplying ionic content includes a filter housing that has a source of electrolytic ions, wherein water passing through said ion supplying filter housing receives said ionic content.

The system as recited in claim 1 , further comprising a power supply connected for supplying a current for passage between said first electrode and said second electrode.

The system as recited in claim 1 , further comprising a check valve connected between said flow producing device and said steam generating tank.

The system as recited in claim 1 , further comprising an appliance connected to receive steam from said steam generating tank, wherein said appliance is for using steam produced in said steam generating tank.

9. The system as recited in claim 1, wherein said steam generating tank includes a first end cap and a second end cap, wherein said first electrode includes a tubular shell having a first end and a second end, wherein said tubular shell includes a conductive material, wherein said first end cap is attached to said first end of said tubular shell, wherein said second end cap is attached to said second end of said tubular shell, wherein said first end cap and said second end cap are both comprised of a nonconductive material.

10. The system as recited in claim 9, wherein said second electrode is positioned within said tubular shell, wherein said first electrode has an inner diameter and wherein said second electrode has an outer diameter, wherein said outer diameter of said second electrode is less than said inner diameter of said tubular shell such that a gap is formed between said first electrode and said tubular shell for receiving the electrolytic solution, wherein current passing between said first electrode and said second electrode travels through the electrolytic solution in said gap to heat said electrolytic solution.

11. The system as recited in claim 10, wherein said steam generating tank includes an expansion chamber, wherein said expansion chamber extends above at least one from the group consisting of said first electrode and said second electrode for receiving steam generated from said heating said electrolytic solution.

12. The system as recited in claim 10, wherein said second electrode has a circular

cross-sectional shape.

13. The steam generator system as recited in claim 1, wherein said heating tank comprises a housing and a cover, wherein said housing includes sidewalls and a bottom, wherein said housing is comprised of a nonconductive material, wherein said cover is removably attachable on said housing, wherein said cover includes a peripheral gasket between said cover and said housing for forming a water-tight seal.

14. The system as recited in claim 13, wherein said first electrode and said second electrode are rectangular-shaped.

15. The system as recited in claim 14, wherein at least one from the group consisting of said first electrode and said second electrode includes a notch along a lower edge to permit passage of the electrolytic solution.

A system for generating steam from an electrolytic solution, comprising a steam generating tank, wherein said steam generating tank includes a first electrode and a second electrode, wherein said first electrode and said second electrode are arranged to contact the electrolytic solution when the electrolytic solution is provided to said steam generating tank and when said first and said second electrodes are connected to a source of AC electrical power, wherein electrical current flows between said first electrode and said second electrode through the electrolytic solution and wherein said electrical current heats the electrolytic solution to produce the steam, wherein flow of electrical current automatically stops when all electrolytic solution in said steam generating tank has been converted to steam.

17. The system as recited in claim 16, wherein no electronic controller is provided that regulates electrical current flowing between said first electrode and said second electrode.

18. The system as recited in claim 16, wherein control over operation is exclusively provided by at least one from the group consisting of connecting and disconnecting said source of AC electrical power for providing current flowing between said first electrode and said second electrode while electrolytic solution remains in said steam generating tank.

19. The system as recited in claim 16, further comprising a supply line, a quick connect

coupling, and an appliance, wherein said appliance is connected to receive steam from said steam generating tank through said supply line and said quick connect coupling, wherein said appliance is for using steam produced in said steam generating tank.

20. The system as recited in claim 16, wherein said first electrode and said second electrode are pencil shaped.

21. The system as recited in claim 16, wherein the electrolytic solution includes at least one from the group consisting of tap water with conductive impurities contained in the tap water and tap water plus table salt added to the water.