Patent Publication Number: US-11646627-B2

Title: Air-cooling system for portable generator

Description:
RELATED APPLICATIONS 
     This application is a continuation and claims priority to U.S. patent application Ser. No. 17/126,927, titled Air-Cooling System for Portable Generator, filed on Dec. 18, 2020 and is incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to equipment to generate electrical power. More specifically, the present disclosure relates to embodiments of a portable electric power generator. More specifically, the present disclosure relates to embodiments of an air-cooling system for a portable electric power generator. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments disclosed herein will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. These drawings depict only typical embodiments, which will be described with additional specificity and detail through use of the accompanying drawings in which: 
         FIG.  1    is an exploded perspective view of an embodiment of an air-cooling system for a portable generator. 
         FIG.  2    is a perspective view of an embodiment of a cabinet of the portable generator of  FIG.  1   . 
         FIG.  3    is a perspective view of an embodiment of a chassis of the cabinet of  FIG.  2   . 
         FIG.  4    is perspective view of an inverter airflow duct of the air-cooling system of  FIG.  1   . 
         FIG.  5    is a perspective view of an engine airflow duct of the air-cooling system of  FIG.  1   . 
         FIG.  6 A  is a front view of an embodiment of an outer duct of an outflow duct of the air-cooling system of  FIG.  1   . 
         FIG.  6 B  is a perspective back view of the outer duct of  FIG.  6 A . 
         FIG.  6 C  is a front view of an embodiment of an inner duct of the outflow duct of the air-cooling system of  FIG.  1   . 
         FIG.  6 D  is a perspective back view of the inner duct of  FIG.  6 C . 
         FIG.  7 A  is a front view of an embodiment of a damping fan of the air-cooling system of  FIG.  1   . 
         FIG.  7 B  is a perspective back view of the damping fan of  FIG.  7 A . 
         FIG.  8    is a perspective view of an embodiment of a connecting flange of the air-cooling system of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION 
     In certain instances, a portable electric power generator can be used to provide electrical power when electrical power from a central electrical grid is not available. For example, a portable electric power generator can be used during outdoor events, camping, tailgating, and an unexpected interruption of electrical power from the power grid. In some embodiments, the portable electric power generator includes a combustion engine configured to drive an alternator. The combustion engine can utilize any suitable combustible agent, such as gasoline, propane, and natural gas. The alternator can produce alternating current electricity. In other embodiments, the alternating current electricity can be converted to direct current electricity. In still other embodiments, the direct current electricity can be converted back to alternating current electricity utilizing an inverter. 
     Embodiments herein describe portable electric power generators. In some embodiments within the scope of this disclosure, the generators include a cabinet. Disposed within the cabinet are a combustion engine and an alternator configured to generate electrical power. The generators further include an air-cooling system configured to guide air over the engine to cool the engine. In some embodiments within the scope of this disclosure, the air-cooling system can include an air inlet to allow ambient temperature air to enter the cabinet, an engine airflow duct to guide air over the engine, and an air outflow duct to guide airflow out of the cabinet. A damping cooling fan can be coupled to the engine and configured to draw the ambient temperature air into the cabinet through the air inlet, over the engine and alternator to draw heat from the engine and alternator, and push the heated air into the air outflow duct and out of the cabinet. In other embodiments, the air-cooling system can include an inverter duct configured to guide airflow over an inverter to draw heat from the inverter. 
     In use, in embodiments within the scope of this disclosure, the engine may be started. When running, the engine can rotate the damping fan. When rotated, the damping cooling fan may draw ambient temperature air through the air inlets into the cabinet. In some embodiments, the air may flow through the inverter duct and over the inverter. The air from the inverter duct can be directed toward the engine and be guided by the engine duct over a cylinder head and cylinder block to draw heat from the cylinder head and the cylinder block. The heated air can flow from the engine duct, over the alternator, and to the outflow duct. The air may flow through the outflow duct and exit the outflow duct through an airflow outlet to the atmosphere. 
       FIG.  1    illustrates an embodiment of an air-cooling system for a portable generator.  FIG.  2    illustrates an embodiment of a cabinet of the portable generator.  FIG.  3    illustrates an embodiment of a chassis of the cabinet of the portable generator.  FIG.  4    illustrates an inverter airflow duct of the air-cooling system.  FIG.  5    illustrates an engine airflow duct of the air-cooling system.  FIGS.  6 A- 6 D  illustrate embodiments of an outer duct and an inner duct of an outflow duct of the air-cooling system.  FIGS.  7 A and  7 B  illustrate an embodiment of a damping fan of the air-cooling system.  FIG.  8    illustrates an embodiment of a connecting flange of the air-cooling system. In certain views each device may be coupled to, or shown with, additional components not included in every view. Further, in some views only selected components are illustrated, to provide detail into the relationship of the components. Some components may be shown in multiple views, but not discussed in connection with every view. Disclosure provided in connection with any figure is relevant and applicable to disclosure provided in connection with any other figure or embodiment. 
       FIG.  1    illustrates an exploded view of an embodiment of a portable generator unit  100 . As illustrated, the portable generator unit  100  can include a control module  105 , a cabinet  110 , an engine  115 , an alternator  120 , and an air-cooling system  130 . The cabinet may include a chassis  111  and an upper cabinet  112 . The engine  115  can include a cylinder head  116  and a cylinder block  117 . The alternator  120  may include a stator  121 , a rotor  122 , an insulation ring  161 , and a connecting flange  123 . The air-cooling system  130  can include a first air inlet  131 , a second air inlet  132 , an airflow outlet  133 , an engine airflow duct  150 , an outflow duct  160 , and a damping cooling fan  190 . The outflow duct  160  may include an outer duct  170  and an inner duct  180 . Alternatively, in some embodiments, the portable generator unit  100  may include an electrical inverter  125  and the air-cooling system  130  may include an inverter airflow duct  140 . 
     The engine  115  may be an internal combustion engine that uses a combustible energy source, such as gasoline, natural gas, or propane, to operate. The engine  115  can be a two-stroke or a four-stroke engine. An output of the engine  115  can range from about 1 horsepower to about 15 horsepower. 
     The stator  121  of the alternator  120  may include magnetic poles. The number of magnetic poles can range from about 12 to about 72. The rotor  122  of the alternator  120  may include permanent magnets or electromagnets. The number of magnets can range from about 6 to about 36. The alternator  120  can be configured to output an alternating current (AC). The output can range from about 1,000 watts to about 15,000 watts. The insulation ring  161  may circumferentially surround the alternator  120  and be disposed between the alternator  120  and the outflow duct  160 . The insulation ring  161  can be formed of any suitable material configured to insulate heat and guide the airflow. For example, the material may be any one of steel or heat resistance plastic. Other materials are contemplated. 
     The electrical inverter  125  may be configured to invert direct current to stable alternating current. The electrical inverter  125  can include airflow fins to facilitate convection cooling of the electrical inverter  125 . 
     The control module  105  can be configured to control any one of a key fob remote control system, an electric control system, an auto choke system, a fuel supply system, and a battery charging system. The control module  105  can include a processor configured to be pre-programmed and/or configured to be programmed by the user. The control module  105  may be hard wired to communicate with the various systems or may communicate with the systems wirelessly. 
       FIG.  2    illustrates the cabinet  110  of the portable generator unit  100 . In certain embodiments, the portable generator unit  100  may not include the cabinet  110  and may be configured as an “open frame” portable generator unit. As illustrated, the cabinet  110  can include the chassis  111  and the upper cabinet  112 . The cabinet  110  may be formed of any material suitable of withstanding high temperatures and harsh environmental conditions. For example, the cabinet can be formed of fiberglass, steel, aluminum or plastic. The chassis  111  may be of a unibody construction and include features such as holes, slots, etc., for securement of components of the portable generator unit  100  within the cabinet  110 . In some embodiments, the upper cabinet  112  may be of a unibody construction. In other embodiments, the upper cabinet  112  can include two, three, four, or more panels coupled together to form the upper cabinet  112 . In certain embodiments, insulation panels may be disposed on an inside surface of the upper cabinet. The insulation panels can absorb noise generated by the engine  115  and other components of the portable generator unit  100 . The insulation panels may also prevent an exterior surface of the upper cabinet  112  from heating to avoid burning a user if touched. 
       FIGS.  3 - 8    illustrate embodiments of components of the air-cooling system  130 . The air-cooling system  130  can be configured to guide or direct airflow within the cabinet  110  to convection cool the operational components of the portable generator unit  100 , such as the engine  115 , the alternator  120 , and the electrical inverter  125 .  FIG.  3    illustrates the first air inlets  131  and the second air inlets of the air-cooling system  130 . As illustrated, the first air inlets  131  and the second air inlets  132  can be disposed in a bottom portion of the chassis  111 . The first air inlets  131  can allow ambient temperature air to enter the cabinet  110  as a first airflow. The second air inlets  132  can allow ambient temperature air to enter the cabinet  110  as a second airflow. The air inlets  131 ,  132  are depicted as a plurality of elongate slots configured to allow the ambient temperature air to pass through the slots. In other embodiments, the air inlets  131 ,  132  may include any suitable shape to allow the passage of the ambient temperature air. For example, the shape of the air inlets  131 ,  132  may be circular, oval, triangular, and square. Other suitable shapes are contemplated. Each of the air inlets  131 ,  132  includes an open area adequate to allow an airflow into the cabinet. The open area of the air inlets  131  can greater than 85 square centimeters and the open area of the air inlets  132  can be greater than 10 square centimeters. 
     The chassis  111  can further include an airflow outlet  133  in the bottom portion of the chassis  111 . The airflow outlet  133  can be in fluid communication with the outflow duct  160  such that heated air can be discharged from the outflow duct  160  through the airflow outlet  133 . The airflow outlet  133  can be of any suitable shape to conform to the outflow duct  160 . 
       FIG.  4    illustrates the inverter airflow duct  140  of the air-cooling system  130 . As illustrated, the inverter airflow duct  140  can include a vertical portion  141  disposed over the first air inlets  131  and coupled to the chassis  111 . A cylindrical portion  142  may be disposed on top of the vertical portion  141 . The inverter  125  can be disposed within the inverter airflow duct  140  and over the first air inlets  131 . The inverter airflow duct  140  can be configured to guide or direct the first airflow from the first air inlets  131 , over fins  126  of the inverter  125 , and out an open end  143  of the cylindrical portion  142  toward the engine  115 . As the first airflow passes over the fins  126 , heat produced by the inverter  125  can be drawn off the fins  126  by convection cooling and transferred to the air of the first airflow. The convection cooling may cool or decrease the temperature of the electrical inverter  125  by a temperature ranging from about 0 degrees Centigrade to about 30 degrees Centigrade. 
       FIG.  5    illustrates the engine airflow duct  150  of the air-cooling system  130 . As illustrated, the engine airflow duct  150  can include a first portion  151 , a second portion  152 , and a third portion  153  coupled together and disposed at least partially around the engine  115 . The engine airflow duct  150  may be configured to guide or direct the first airflow received from the inverter airflow duct  140  over the cylinder head  116  and the second airflow over the cylinder block  117  to convection cool the engine  115  and to prevent the heated air of the first and second airflows from dispersing throughout the cabinet  110 . The convection cooling may cool or decrease the temperature of the engine  115  by a temperature ranging from about 0 degrees Centigrade to about 10 degrees Centigrade. 
       FIGS.  6 A- 6 D  illustrate an embodiment of the outflow duct  160  of the air-cooling system  130 .  FIG.  6 A  illustrates an exterior of the inner duct  180  and  FIG.  6 B  illustrates an interior of the inner duct  180 . As illustrated, the inner duct  180  can include a first airflow passage  181 , a second airflow passage, a first airflow channel  183 , a second airflow channel  184 , an airflow distributor  185 , and an airflow outlet  186 . The inner duct  180  may include any suitable material, such as aluminum or steel, and be formed using any suitable technique, such as stamping. Other materials and forming techniques are contemplated. The first airflow passage  181  may be disposed to a side of the inner duct  180  and have a general rectangular shape. The first airflow passage  181  can be configured to receive the heated first airflow from the cylinder head  116  of the engine  115  and guide or direct the first airflow into the first airflow channel  183 . 
     The second airflow passage  182  can be disposed on an opposite side of the inner duct  180  wherein it is in alignment with the alternator  120 . The second airflow passage  182  may have a generally circular shape. The second airflow passage  182  may be sized to receive the alternator  120  and the damping cooling fan  190 . A diameter of the second airflow passage  182  can range from about 10 centimeters to about 50 centimeters. The second airflow passage  182  may be configured to receive the second airflow from the cylinder block  117  of the engine  115  and guide or direct the second airflow into the first airflow channel  183 . 
     The first airflow channel  183  can be in fluid communication with the first airflow passage  181  and can be defined by a side wall  189  and the airflow distributor  185 . The airflow distributor  185  can divide the first airflow channel  183  from the second airflow channel  184  wherein air flowing through the first airflow channel  183  cannot substantially mix with air flowing through the second airflow channel  184 . The airflow distributor  185  may include an arcuate shape having a radius ranging from about 14 centimeters to about 24 centimeters. The airflow distributor  185  may divide the airflow outlet  186  into two outlets, one in fluid communication with the first airflow channel  183  and the second in fluid communication with the second airflow channel  184 . 
     The second airflow channel  184  can be in fluid communication with the second airflow passage  182  and can be defined by a wall  187  having a convex arcuate shape. A radius of the arcuate shape may range from about 5 centimeters to about 30 centimeters. The arcuate shape can provide for a non-turbulent airflow through the second airflow channel  184 . Further, the second airflow channel  184  can be defined by an exterior wall  188 . A thickness of a portion of the exterior wall  188  adjacent the airflow outlet  186  may be tapered toward the airflow outlet  186  to increase a cross-sectional area of the second airflow channel  184 . The increased cross-sectional area may allow the airflow within the second airflow channel  184  to flow towards the airflow outlet  186  with low resistance. The exterior wall  188  may taper from about 2 millimeters to about 6 millimeters to a thickness ranging from about 2 millimeters to about 5 millimeters. 
       FIG.  6 C  illustrates an exterior of the outer duct  170  and  FIG.  6 D  illustrates an interior of the outer duct  170 . As illustrated, the outer duct  170  can include an airflow passage  171 . The outer duct  170  may include any suitable material, such as aluminum or steel, and be formed using any suitable technique, such as stamping. Other materials and forming techniques are contemplated. The outer duct  170  can include an airflow passage  171 , a first airflow channel  172 , a second airflow channel  173 , an airflow distributor  174 , and an airflow outlet  175 . The airflow passage  171  can include an exterior opening  176  and may be disposed to a side of the outer duct  170  such that it is in alignment with alternator  120 . The airflow passage  171  may be sized to receive the damping cooling fan  190  and the alternator  120 . A diameter of the airflow passage can range from about 10 centimeters to about 50 centimeters. A diameter of the exterior opening  176  may be smaller than a diameter of the damping cooling fan  190 . The diameter of the exterior opening  176  may range from about 10 centimeters to about 60 centimeters. The airflow passage  171  can be configured to receive the second airflow from the engine  115  and guide or direct the second airflow into the second airflow channel  173 . 
     The first airflow channel  172  can be in fluid communication with the first airflow passage  181  and the first airflow channel  183 . The first airflow channel  172  may be defined by a side wall  179  and the airflow distributor  174 . The airflow distributor  174  can divide the first airflow channel  172  from the second airflow channel  173  wherein air flowing through the first airflow channel  172  cannot substantially mix with air flowing through the second airflow channel  173 . The airflow distributor  174  may include an arcuate shape having a radius ranging from about 5 centimeters to about 30 centimeters. The airflow distributor  174  may divide the airflow outlet  175  into two outlets, one in fluid communication with the first airflow channel  172  and the second in fluid communication with the second airflow channel  173 . 
     The second airflow channel  173  can be in fluid communication with the second airflow passage  182  and the second airflow channel  184 . The second airflow channel  173  may be defined by a wall  177  having a convex arcuate shape. A radius of the arcuate shape may range from about 8 centimeters to about 30 centimeters. The arcuate shape can provide for a non-turbulent airflow through the second airflow channel  173 . Further, the second airflow channel  173  can be defined by an exterior wall  178 . A thickness of a portion of the exterior wall  178  adjacent the airflow outlet  175  may be tapered toward the airflow outlet  175  to increase a cross-sectional area of the second airflow channel  173 . The increased cross-sectional area may allow the airflow within the second airflow channel  173  to flow towards the airflow outlet  175  with low resistance. The exterior wall  178  may taper from a thickness ranging from about 2 millimeters to about 6 millimeters to a thickness ranging from about 2 millimeters to about 5 millimeters. 
       FIGS.  7 A and  7 B  illustrate the damping cooling fan  190  of the air-cooling system  130 . The damping cooling fan  190  can be coupled to and rotated by the engine  115 . The damping cooling fan  190  may be formed of any suitable rigid material. For example, the rigid material can be a metal, such as aluminum or steel, or a reinforced plastic, such as polycarbonate, or other plastic. Other materials are contemplated. As illustrated, the damping cooling fan  190  can include a damping portion  191 , a plurality of fan blades  192 , and a choke ring  195 . The damping portion  191  can be a circular plate extending radially outward from a central axis of the damping cooling fan  190 . A diameter of the damping portion  191  can range from about 10 centimeters to about 50 centimeters. The damping portion  191  can prevent air from passing between the fan blades  192  adjacent the central axis of the damping cooling fan  190 . 
     The fan blades  192  may be coupled to the damping portion  191  and have a height ranging from about 2.5 centimeters to about 6 centimeters. A radial inner portion  193  of the fan blades  192  may be disposed at an angle ranging from 100 degrees to about 165 degrees relative to a perpendicular plane extending through the central axis. A distal portion  194  of the fan blades  192  can include an arcuate shape. The arcuate shape can include a radius ranging from about 11 centimeters to about 31 centimeters. The arcuate shape may be configured to capture air and direct the air into the second airflow channels  173 ,  184  of the outflow duct  160 . The choke ring  195  may be coupled to the peripheral ends of the fan blades  192 . The choke ring  195  can have a width ranging from about 5 millimeters to about 20 millimeters. The choke ring  195  may prevent airflow from flowing toward the alternator  120  and guide or direct airflow into the second airflow channels  173 ,  184 . 
       FIG.  8    illustrates the connecting flange  123  of the alternator  120 . The connecting flange  123  may be configured to couple the stator  121  to the engine  115  to prevent the stator  121  from rotating. As illustrated, the connecting flange can include airflow passages  124  configured to allow the first airflow to flow through the connecting flange  123 . The connecting flange  123  can be formed of any suitable material, such as aluminum or steel. Other materials are contemplated. 
     In use, the engine may be started by an electric starter or pull starter. When running, the engine can rotate the damping fan. When rotated, the damping fan may draw ambient temperature air through the first air inlets into the cabinet to form a first airflow and through the second air inlets into the cabinet to form a second airflow. In some embodiments, the first airflow may flow through the inverter duct and over the inverter. As the first airflow passes over the inverter, heat from the inverter can be transferred to the first airflow. 
     The first airflow can flow from the inverter duct to the engine and be directed or guided by the engine duct over the cylinder head. As the first airflow passes over the cylinder head, heat from the cylinder head can be transferred to the first airflow to further heat the first airflow. The first airflow can flow from the engine duct to the outflow duct. The first airflow may flow through the first airflow passage of the inner duct, into the first airflow channel, and through the airflow outlet into the atmosphere. 
     The second airflow can flow over the cylinder block. As the second airflow flows over the cylinder block, heat from the cylinder block may be transferred to the second airflow. The second airflow can flow from the cylinder block and over the alternator. In some embodiments, the second airflow may flow through the connecting flange. As the second airflow flows over the alternator, heat from the alternator may be transferred to the second airflow. The second airflow can flow from the alternator to the damping fan. The damping portion of the damping fan can prevent the second airflow from passing through the damping fan. The fan blades of the damping fan can direct the second airflow toward the outflow duct and into the second airflow channel. The choke ring of the damping fan may prevent the second airflow from flowing toward the alternator. The second airflow can flow into the second airflow channel and through the airflow outlet into the atmosphere. 
     Any methods disclosed herein comprise one or more steps or actions for performing the described method. The method steps and/or actions may be interchanged with one another. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order and/or use of specific steps and/or actions may be modified. For example, a method of air-cooling a portable generator may include one or more of the following steps: starting a combustion engine disposed within a portable generator cabinet; rotating a damping cooling fan; drawing a first airflow through a first air inlet into the portable generator cabinet; guiding the first airflow over a cylinder head of the combustion engine; guiding the first airflow through a first airflow passage, a first airflow channel, and a first airflow outlet of an air outflow duct; drawing a second airflow through a second air inlet into the portable generator cabinet; drawing the second airflow over a cylinder block of the combustion engine; accelerating the second airflow by rotation of the damping cooling fan; and guiding the second airflow through a second airflow passage, a second airflow channel, and a second airflow outlet of the air outflow duct. Other steps are also contemplated. 
     Embodiments may be understood by reference to the drawings, wherein like parts are designated by like numerals throughout. It will be readily understood by one of ordinary skill in the art having the benefit of this disclosure that the components of the embodiments, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the disclosure, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. 
     Reference throughout this specification to “an embodiment” or “the embodiment” means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, the quoted phrases, or variations thereof, as recited throughout this specification are not necessarily all referring to the same embodiment. 
     Similarly, in the above description of embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim requires more features than those expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. 
     It will be appreciated that various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure. Many of these features may be used alone and/or in combination with one another. 
     The phrases “coupled to” and “in communication with” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interaction. Two components may be coupled to or in communication with each other even though they are not in direct contact with each other. For example, two components may be coupled to or in communication with each other through an intermediate component. 
     “Fluid” is used in its broadest sense, to refer to any fluid, including both liquids and gases as well as solutions, compounds, suspensions, etc., which generally behave as fluids. 
     References to approximations are made throughout this specification, such as by use of the term “substantially.” For each such reference, it is to be understood that, in some embodiments, the value, feature, or characteristic may be specified without approximation. For example, where qualifiers such as “about” and “substantially” are used, these terms include within their scope the qualified words in the absence of their qualifiers. For example, where the term “substantially perpendicular” is recited with respect to a feature, it is understood that in further embodiments, the feature can have a precisely perpendicular configuration. 
     The terms “a” and “an” can be described as one, but not limited to one. For example, although the disclosure may recite a housing having “a stopper,” the disclosure also contemplates that the housing can have two or more stoppers. 
     Unless otherwise stated, all ranges include both endpoints and all numbers between the endpoints. 
     Recitation in the claims of the term “first” with respect to a feature or element does not necessarily imply the existence of a second or additional such feature or element. 
     The claims following this written disclosure are hereby expressly incorporated into the present written disclosure, with each claim standing on its own as a separate embodiment. This disclosure includes all permutations of the independent claims with their dependent claims. Moreover, additional embodiments capable of derivation from the independent and dependent claims that follow are also expressly incorporated into the present written description. 
     Without further elaboration, it is believed that one skilled in the art can use the preceding description to utilize the invention to its fullest extent. The claims and embodiments disclosed herein are to be construed as merely illustrative and exemplary, and not a limitation of the scope of the present disclosure in any way. It will be apparent to those having ordinary skill in the art, with the aid of the present disclosure, that changes may be made to the details of the above-described embodiments without departing from the underlying principles of the disclosure herein. In other words, various modifications and improvements of the embodiments specifically disclosed in the description above are within the scope of the appended claims. Moreover, the order of the steps or actions of the methods disclosed herein may be changed by those skilled in the art without departing from the scope of the present disclosure. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order or use of specific steps or actions may be modified. The scope of the invention is therefore defined by the following claims and their equivalents.