Abstract:
An electrical generator has an internal combustion engine and an alternator mounted to the engine and operative to generate electrical power during running of the engine. The alternator and the engine are arranged vertically to reduce the footprint of the electrical generator. The components of the electrical generator are contained within an enclosure defined by a base panel, a set of upright side panels, and a roof panel. When the roof panel is removed, each of the side panels can be independently removed from engagement with the base panel, which allows for easier access to the components of the electrical generator, such as for maintenance, service, and repair. The components are arranged so that cooling and exhaust air flow paths are defined within the enclosure.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Ser. No. 61/295,961 filed Jan. 18, 2010, the disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
       [0002]    Electrical generators are used in a wide variety of applications. Typically, an electrical generator operates in a stand-by mode wherein the electrical power provided by a utility is monitored such that if the commercial electrical power from the utility fails or is otherwise interrupted for a certain period of time, the engine of the electrical generator is started, either automatically or manually by a customer, causing the electrical generator to supply emergency or backup electrical power. More particularly, the engine drives an alternator to provide electrical current to power selected electrical loads that are connected to the electrical generator, which is typically though a dedicated electrical panel, i.e., transfer panel. 
         [0003]    When the electrical power generated by the alternator reaches a predetermined voltage and frequency desired by the customer, a transfer switch transfers the load imposed by the customer from the commercial power lines to the electrical generator. The electrical generator then supplies electrical power to selected loads, which are typically deemed to be critical loads, such as HVAC equipment, refrigerator(s), lighting, and, if applicable, medical equipment. 
         [0004]    In a typical installation, the electrical generator will be located adjacent an exterior wall of a home, building, garage, or similar structure. Many consumers find the electrical generator aesthetically unappealing and, as such, will often place the electrical generator in a location that is hidden from view altogether or use various plantings, e.g., shrubs, around the electrical generator to soften its view. Decreasing the size, or footprint, of the electrical generator would make it easier to “hide” the electrical generator; however, reducing the size of the electrical generator can result in an electrical generator that provides less electrical power. 
         [0005]    One of the challenges faced by engineers in designing smaller electrical generators without sacrificing power output is preventing overheating of various temperature sensitive components of the electrical generator. If these components are not cooled effectively, the components may fail and render the electrical generator inoperative. While effective in providing thermal control, heat sinks, fans, and coolant circulations systems can ultimately add to the size of the electrical generator and, in the case of using multiple or larger fans, greater noise emissions. 
         [0006]    In addition to smaller electrical generators, many consumers are demanding electrical generators that are constructed to be more user-friendly. That is, the components of conventional electrical generators will typically be contained within an integrated, and often heavy, housing that is difficult for a consumer to disassemble or remove to access the components of the electrical generator, such as for inspection, maintenance, and service. Alternately, many electrical generators will have dedicated access panels that may be removed to provide user access to selected components of the electrical generator. In both instances, servicing or repairing the electrical generator can be difficult for those of conventional design. 
         [0007]    The present invention is directed to a fuel powered, electrical generator and, more particularly, to a vertical fuel powered, electrical generator. The invention provides an electrical generator having a smaller footprint than conventional horizontal generators and has a unique frame construction that allows for easier access to the components of the electrical generator, such as for maintenance, service, and repair. Additionally, in accordance with one embodiment of the invention, the electrical generator has an internal combustion engine with a crankcase that is configured in a manner that allows the alternator of the electrical generator to be mounted directly to the crankcase. In this embodiment, the invention avoids the need for a separate mount or similar member that is otherwise typically used to couple the alternator to the engine. Furthermore, as will be described more fully below, the present invention provides an electrical generator having improved airflow characteristics for better thermal control. 
         [0008]    Therefore, in accordance with one aspect of the invention, an electrical generator includes an internal combustion engine that provides mechanical energy to an alternator mounted directly to the engine and that generates electrical power from the mechanical energy. 
         [0009]    In accordance with another aspect of the invention, an electrical generator has an internal combustion engine and an alternator mounted to the engine. The engine has an output shaft that extends along a vertical axis and interconnects with a rotor of the alternator. 
         [0010]    According to another aspect of the invention, an electrical generator includes an engine and an alternator operatively associated with the engine to create electric power during operation of the engine. The electrical generator further includes an enclosure for the engine and the alternator, and has a base panel, a roof panel, and a plurality of side panels. Openings are formed in at least one of the side panels. The electrical generator further comprises an engine and alternator cooling system configured to provide cooling air to the engine and the alternator. The cooling system provides a first cooling path in which air is drawn through an opening formed in a side panel of the enclosure and is pulled downward through the engine to provide cooling for the engine and a second cooling path in which air is drawn through an opening formed in a side panel of the enclosure and is pulled downward through the alternator to provide cooling for the alternator. Some of the air that is passed through engine or the alternator is used to provide cooling for other components of the electrical generator contained within the enclosure. 
         [0011]    Other objects, features, and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0012]    The drawings illustrate the best mode presently contemplated of carrying out the invention. 
           [0013]    In the drawings: 
           [0014]      FIG. 1  is a schematic representation of a standby or emergency power supply system that supplies electrical power to an electrical system during interruption of utility power; 
           [0015]      FIG. 2  is an isometric view of an electrical generator for use with the emergency power supply system of  FIG. 1  according to one embodiment of the invention; 
           [0016]      FIG. 3  is an exploded view of an enclosure structure of the electrical generator of  FIG. 2 ; 
           [0017]      FIG. 4  is an exploded view of a power block of the electrical generator of  FIG. 3  having a vertically oriented internal combustion engine and alternator according to one aspect of the invention; 
           [0018]      FIG. 5  is an exploded view of a cooling and exhaust system for the power block of  FIG. 4  according to another aspect of the invention; 
           [0019]      FIG. 6  is a section view of the electrical generator taken along line  6 - 7  of  FIG. 2  and annotated to show an air flow path along which air can be drawn into the engine and alternator of the electrical generator; 
           [0020]      FIG. 7  is a top view of the electrical generator with a roof or cover panel removed and annotated to show a cooling air flow path to provide cooling air around a muffler; 
           [0021]      FIG. 8  is a section view similar to that shown in  FIG. 6  but annotated to show an air flow path along which air can be drawn into an air box of the electrical generator; and 
           [0022]      FIG. 9  is a section view of the electrical generator taken along line  9 - 9  of  FIG. 2  and annotated to show an air flow path along which air exhausted from the electrical generator can be vented to atmosphere. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]      FIG. 1  shows a power inlet arrangement for interconnecting an electrical generator  10  with a main electrical panel or load center  12  located in the interior of a building  14 . In the power inlet arrangement of  FIG. 1 , a power transfer panel  16  is mounted adjacent main panel  12 , and is interconnected therewith via a series of wires enclosed by a conduit  18  extending between main panel  12  and transfer panel  16 . 
         [0024]    A power inlet box  20  is mounted to the wall of building  14 , shown at  22 . Power inlet box  20  includes an external housing including a series of walls such as  24 , and a receptacle  26  mounted to a front wall of the housing. A cover  28  is mounted to the front wall of the housing via a hinge structure, and is movable between an open position as shown in  FIG. 1  and a closed position in which cover  28  encloses receptacle  26  when not in use. A conduit  30  extends between inlet box  20  and a junction box  32 , and a flexible cord  38  is attached at one end to junction box  32 . At its opposite end, flexible cord  38  has a connector  42  engageable with a power inlet receptacle provided on transfer panel  16 . Appropriate wiring and connections are contained within inlet box  20 , conduit  30  and junction box  32  for providing an electrical path between inlet box  20  and transfer panel  16  when cord  38  is engaged with the inlet receptacle of transfer panel  16 . 
         [0025]    A power cord  44  extends between generator  10  and power inlet box  20 . Cord  44  includes a plug  46  at one end, which is engageable with the power outlet of generator  10 . Cord  44  further includes a connector  48  at the end opposite plug  46 . Connector  48  is engageable with receptacle  26  for transferring power generated by generator  10  to power inlet box  20 , which is then supplied through the wiring in conduit  30 , junction box  32 , cord  38  and connector  42  to transfer panel  16 , and from transfer panel  16  through the wiring in conduit  18  to main panel  12 . In this manner, generator  10  functions to provide power to selected circuits of main panel  12  during a power outage. 
         [0026]    In a preferred embodiment, the electrical generator  10  is caused to run automatically upon the interruption of utility power. In this regard, a customer is not required to manually start the electrical generator  10  to commence the supply of standby electrical power. As known in the art, when utility power is interrupted, the transfer panel  16  transmits a signal to the electrical generator  10  which causes the electrical generator  10  to start. 
         [0027]    Turning now to  FIGS. 2-5 , electrical generator  10  has an enclosure  50  that is generally comprised of a base panel  52 , end panels  54 ,  56 , side panels  58 ,  60 , and a cover or roof panel  62 . The enclosure  50  further includes four corner panels  64 ,  66 ,  68 , and  70 . The end and side panels may include louvers  72  and  74 , for example, for drawing air into and exhausting air from the interior volume formed by the enclosure  50 . The end and side panels are supported uprightly by the base panel  52 . Each corner panel is interfit between an end panel and an adjacent side panel, and includes channels  76 ,  FIG. 8 , into which panels are to be drop loaded when assembling the enclosure  50 . Thumb screws  78  are used to fasten the roof panel  62  to the corner panels  64 ,  66 ,  68 , and  70 . The thumb screws  78  are designed to be hand tightened which allows a user, such as a homeowner or service technician, to remove the roof panel  62  in a tool-free manner. Additionally, since the end and side panels are drop-loaded into engagement with their respective corner panels, the end and side panels can be individually and independently raised and withdrawn from the base panel for servicing of the electrical generator  10 . 
         [0028]    With particular reference to  FIGS. 2-7 , an internal combustion engine  80 , having a vertically oriented output shaft  82 , and an alternator  84  are mounted within the interior volume of the enclosure using steel tubing  86 . More particularly, the alternator  84  is coupled to the engine  80 , which is supported by an upper portion of the steel tubing. In addition, a heat shield  88  and a muffler  90  are mounted to the alternator  84 . A shroud  92  is coupled to the steel tubing to encase the muffler  90  between an inner surface of the shroud  92  and an outer surface of the heat shield  88 . An air box  94  is provided and may be mounted to the engine or the steel tubing. The air box  94  preferably contains upper and lower members  94 ( a ) and  94 ( b ), and house an air filter  95 . Rubber pads  96  are interconnected between the engine  80  and the steel tubing  86  to reduce vibration of the steel tubing during operation of the engine. A spacer ring  98  fits over the alternator  84 . 
         [0029]    The alternator  84  generally consists of a generally annular stator  100  and a rotor (not numbered) positioned radially inward of the stator. The adapter  98  and an upper portion  102 ( a ) of a bearing carrier  102  define a housing for the stator  100 . The rotor (not numbered) is coupled to the output shaft  82  of the engine  80  such that during operation of the engine  80 , the rotor rotates to generate an electric current in the stator  100 . The stator  100  is mounted directly to a lower portion of adapter  98  which is then coupled to the engine  80 . 
         [0030]    The electrical generator  10  includes a fan  104  that is disposed in a generally annular volume defined by the bearing carrier  102  and is coupled to rotor bolt  106  that is rotatably coupled to the rotor. In this regard, the fan  104  will rotate during operation of the engine  80  and the rotor (not numbered). Bolts  108  extend through bearing carrier  102  and elongated openings  110  formed in the outer surface of the spacer  98  and ultimately thread into holes (not numbered) formed in the lower portion of the engine  80  to couple the alternator to the engine. It will thus be appreciated that the alternator  84  is mounted between the engine  80  and the fan  104 . 
         [0031]    Turning now to  FIG. 6 , during generator operation, air is drawn from outside the enclosure  50  through openings formed in end panels, e.g., louvers  72  in end panels  54  and  56  along air flow path  111 , and through an air inlet  112  that is flow coupled to the alternator  84  by duct  114 . In this regard, the drawn air passes through the duct  114  and through openings  116  formed in the spacer ring  98 , and is pulled downward by rotation of the fan  104  past the rotor and out of the bearing carrier  102  at air outlets  118 , generally along air flow path  120 . The drawn air provides cooling for the alternator during its operation. After the air is passed through the alternator and blown through air outlet  118 , some of the air passes over/around the muffler  90  to provide cooling for the muffler. 
         [0032]    Cooling air for the engine  80  is drawn through openings  121  and  122  formed in end panels  54 ,  56 , respectively, and along flow paths  123  and  124 , and is used to cool the engine during its operation. The cooling air that is passed through the engine is also directed toward the muffler  90  to provide cooling of the muffler  90  along flow paths  126  and  128 , as shown in  FIG. 7 . 
         [0033]    Turning to  FIG. 8 , air for combustion is also drawn through openings  121  formed in end panel  56  along air flow path  130 . Air along the air flow path  130  provided to the air box  94  whereupon the air is filtered by filter  95  before being used for combustion by the engine. Now referring to  FIG. 9 , exhaust from combustion is fed to the muffler  90  and ultimately exhausted through exhaust pipe  132 . The exhaust pipe  132  then passes the exhausted air away from the alternator  84  toward the openings  134  and  136  formed in side panels  58  and  60  along flow paths  138  and  140  whereupon the exhausted air is passed to atmosphere. As shown in  FIG. 9 , the exhaust pipe  132  extends along a horizontal plane. 
         [0034]    Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.