Abstract:
A barbecue grill comprises a grill grid, a shaft for rotating the grill grid, a barbecue grill housing, such as a fire bowl, having an opening at its bottom portion where the shaft passes through the opening, an ash container removably placed beneath the opening of the fire bowl, and a motor removably coupled to the bottom of the ash container. After the barbecue is finished, the ash container and the motor can be easily removed from the fire bowl.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates to a barbecue grill. More particularly, the present invention relates to a barbecue grill having a rotating grill grid driven by a motor removably attached to the barbecue grill. 
         [0002]    Conventional charcoal barbecue grills with a rotating grill grid have been developed to achieve even cooking results by rotating the grill grid and the food on the grill grid while barbecuing. U.S. Pat. No. 6,929,001 discloses a barbecue grill that realizes an even broiling and subsequent optimal barbecue, and minimizes excessive burning of food on a wire grid plate and consumption of charcoal. The barbecue grill of U.S. Pat. No. 6,929,001 comprises a gridiron disk, a shaft extending from the gridiron disk so that the shaft becomes substantially perpendicular to the gridiron disk, a bowl having a channel where the shaft is detachably received through the channel, and a motor attached to the bowl to generate rotation of the shaft. 
         [0003]    U.S. Pat. No. 5,787,873 discloses a retro-fit barbecue grill grid gear drive assembly for attaching to a common prior-art barbecue stand. The retro-fit barbecue grill grid gear drive assembly of U.S. Pat. No. 5,787,873 comprises an electric gear drive motor or a reversible gear drive motor attached to a heat-sink perforated plate and protected in a housing. A housing extension pipe is fitted into a hole made in a fire bowl. The motor turns a drive shaft and a clamp type drive head, or other drive head and a grill grid at about 1 RPM. 
         [0004]    However, the conventional charcoal barbecue grills discussed above have drawbacks. For example, in these conventional charcoal barbecue grills with rotating grill, the motor is fixed to the bottom of the barbecue grill. It is not convenient to remove the motor from the barbecue grill when it is not in use. In addition, as the ash is left inside the barbecue grill, it is not easy to dispose the ash after the barbecue grill is used. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention is contrived to overcome the drawbacks of conventional barbecue grills. One aspect of the invention is to provide a barbecue grill with a rotating grill grid that is driven by a motor removably attached to the barbecue grill and powered by an AC power or a battery. Another aspect of the present invention is to provide a barbecue grill wherein the ash is collected in a container positioned outside the barbecue grill housing so that it is easy to dispose the ash. 
         [0006]    The barbecue grill according to the present invention comprises a grill grid, a shaft for rotating the grill grid, a barbecue grill housing, such as a fire bowl, having an opening at its bottom portion where the shaft passes through the opening, an ash container removably attached to the fire bowl beneath the opening of the fire bowl, and a motor removably attached to the bottom of the ash container to generate rotation of the shaft so as to rotate the grill grid. The shaft passes through the ash container and is engaged at one end with the motor. In use, the ash container is removably attached to the bottom of the fire bowl, and the motor is removably attached to the bottom of the ash container, for example, through a sliding mechanism. After the barbecue is finished, the ash container and the motor can be easily removed from the fire bowl for disposing ash and for storage. When an ash container is provided, the center opening at the bottom of the fire bowl is made large enough for ash to fall into the ash container through the center opening, and no additional air holes are needed at the bottom portion of the fire bowl. 
         [0007]    The barbecue grill further includes a fire grid for supporting a charcoal fire. The shaft passes through the fire grid. The present invention can use any conventional fire bowls and fire grids that are suitable for charcoal fire. 
         [0008]    In another embodiment, no separate ash container is provided. The barbecue grill according to this embodiment comprises a grill grid, a shaft for rotating the grill grid, a barbecue grill housing, such as a fire bowl, having an opening at its bottom portion where the shaft passes through the opening, and a motor removably attached to the bottom of the fire bowl to generate rotation of the shaft so as to rotate the grill grid. In this case, additional air holes are formed on the bottom portion of the fire bowl, and the center opening on the bottom of the fire bowl is sealed around the shaft so that ash will not fall through the center opening. 
         [0009]    The present invention will be described in more details in connection with by the following drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    These and other features, aspects and advantages of the present invention will become better understood with reference to the accompanying drawings, wherein: 
           [0011]      FIG. 1  is an exploded view showing a barbecue grill according to the present invention; 
           [0012]      FIG. 2  is a perspective view of a flange for attaching an ash container to an fire bowl of the present invention; 
           [0013]      FIG. 3  is a perspective view of an ash container of the present invention; 
           [0014]      FIG. 4  is a cross-sectional view of a fire bowl and a flange attached to the fire bowl of the present invention; 
           [0015]      FIG. 5  is a cross-sectional view of the ash container of the present invention; 
           [0016]      FIG. 6  is a perspective view of a washer placed between an ash container and a connection piece of the present invention; 
           [0017]      FIG. 7  is a perspective view of a connection piece between an ash container and a motor of the present invention; 
           [0018]      FIG. 8  is a perspective view of a motor used in the present invention; 
           [0019]      FIG. 9  is a perspective view of a shaft of the present invention; 
           [0020]      FIG. 10  is perspective view of a protection sleeve of the present invention; and 
           [0021]      FIG. 11  is a cross-sectional view showing the rotary support mounted on a fire bowl of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0022]      FIG. 1  shows an assembly view of a barbecue grill  1  according to the present invention in a vertically exploded alignment. As shown, the barbecue grill  1  includes a grill grid  2 , a fire grid  4 , and a fire bowl  6 . Fire bowl  6  has an opening  605  at the center of its bottom. A flange  8  is fixed to the bottom of fire bowl  6  from beneath and aligned with the opening  605 . An ash container  10  is removably attached to flange  8 . A connection piece  12  is fixed to the bottom of ash container  10 . A motor  14  is removably attached to the connection piece  12 . A shaft  16  passes through fire bowl  6  and ash container  10 , and engages with grill grid  2  at its upper end and with motor  14  at its lower end. Charcoal ash falls from fire bowl  6  into ash container  10  through opening  605 . Opening  605  also functions as an air hole for supplying air to the charcoal fire on fire grid  4 . Therefore, no additional air holes are required on the sidewall of fire bowl  6 . 
         [0023]      FIG. 2  shows a flange  8  according to an embodiment of the present invention for removably attaching ash container  10  to the bottom of fire bowl  6 . In this embodiment, flange  8  has a cylindrical sidewall  84  connected to an inward extending upper edge  82  and an outward extending lower edge  86 . Through holes  88  are formed on the inward extending upper edge  82 . Holes  607  are formed on the fire bowl  6  corresponding to the locations of holes  88 . There are two parallel straight portions  87  formed on opposite sides of the lower edge  86  for receiving ash container  10 . As shown in  FIG. 4 , flange  8  is fixed to the bottom of fire bowl  6  with screws  606  through holes  607  on the fire bowl  6  and holes  88  on the flange  8 . Alternatively, flange  8  can be welded to the bottom of fire bowl  6 . In this case, the inward extending upper edge  82  and through holes  88  will not be necessary. Alternatively, the inward extending upper edge  82  can be made outward extending like the outward extending lower edge  86 . Also, instead of a continuous edge, the inward extending upper edge  82  can be made of several separate pieces each containing one through hole  88 . Flange  8  can be replaced with two separate pieces fixed to two opposite sides of the opening  605 , which have the same function as the two parallel straight portions  87 . 
         [0024]    As shown in  FIGS. 3 and 5 , ash container  10  has cylindrical body  101  with an outward extending upper edge  102 . A pair of hooks  103  are formed on opposite sides of the outward extending upper edge  102 . When in use, the pair of hooks  103  engage with corresponding straight portions  87  of the lower edge  86  of flange  8 , so that ash container  10  can be easily slid onto or off flange  8  so as to removably attach ash container  10  to fire bowl  6 . Air holes  105  are formed on the upper portion of body  101 . A tube  106  is inserted through a center hole on the bottom of ash container  10  providing a passage for shaft  16 . Tube  106  can be fixed to the bottom of ash container  10  by a washer  11  as described below or by welding. The ash container  10  can also be provided with a handle on body  101 . A stopper  108  is formed on the outward extending upper edge  102  between the pair of hooks  103  for positioning ash container  10  relative to flange  8  by engaging with the outward extending lower edge  86  of flange  8 .  FIG. 3  shows that body  101  has a cylindrical shape, but body  101  can have any desired shape. Alternatively, the outward extending upper edge  102  can be replaced with two separated pieces positioned at two opposite sides of the body  101  which have the same function as the two hooks  103 . Screw holes  107  are provided on the bottom of ash container  10 . 
         [0025]    Various other connection mechanisms between fire bowl  6  and ash container  10  can be used to removably attach ash container  10  to the bottom of fire bowl  6 . For example, flange  8  can be replaced by two separate pieces, each is fixed to the bottom of fire bowl  6  and each has an outward extending edge for engaging with the hook  103  of ash container  10 , or each has an inward extending edge for receiving the outward extending upper edge  102  of ash container  10  (in this case, hooks  13  are no longer needed). In addition, the detachable attachment between the fire bowl  6  and the ash container  10  can be a rotary connection instead of the above discussed sliding connection. For example, instead of hooks  103 , upright protrusions can be provided on the outward extending upper edge  102  of ash container  10 . The upright protrusions may have a shank and a head having a larger dimension or diameter than that of the shank. Corresponding holes with a diameter that allows the head to pass through can be formed on the outward extending lower edge  86  of flange  8 , and each of these corresponding holes is connected to a channel with a width smaller than the diameter of the head, but larger than the diameter of the shank. By inserting the head of the upright protrusions of ash contained 10 into corresponding holes of flange  8  and rotating ash container  10  relative to flange  8 , the shank is slid into a corresponding channel so as to removably lock ash container  10  to flange  8 . 
         [0026]      FIG. 6  shows a washer  11  having a center hole  111  and holes  112 . The tube  106  is in tight fit with the center hole  111 . When assembled, tube  106  is pressed into center hole  111  and fixed therein. Washer  11  is attached to the outer bottom of container  10  by rivet or screw through holes  112  of the washer  11  and holes  107  on the bottom of the ash container  10 . 
         [0027]    Motor  14  is removably attached to the bottom of ash container  10  through a connection piece  12 . As shown in  FIG. 7 , connection piece  12  has an upper plate  121  and a lower plate  122  connected by a meddle portion  123 , such as a vertical wall. A center hole  124  is formed in upper plate  121  for receiving tube  106 . Holes  125  are provided for fixing upper plate  121  to the bottom of ash container  10 . When assembled, the upper plate  121  is riveted or screwed to the washer  11  and the bottom of ash container  10  through holes  125 ,  112  and  107  with the lower end of tube  106  inserted into the center hole  124 . A disk can be provided between the bottom surface of ash container  10  and the upper plate  121 . The lower plate  122  also has a center hole  126  for receiving shaft  16 . 
         [0028]    As shown in  FIG. 8 , motor  14  is provided with a pair of hooks  141  on its upper surface for slidingly engaging with two opposite edges  127  of the lower plate  122  of connection piece  12 . Through the engagement between the two opposite edges  127  of the lower plate  122  of connection piece  12  and the pair of hooks  141  on motor  14 , motor  14  can be easily slid onto or off the connection piece  12 . A rotating head  142  is removably attached to the lower end of shaft  16  to rotate the shaft and grill grid  2 . 
         [0029]    Motor  14  can be powered by either an AC source or a battery, or both. For example, motor  14  can be powered by two 1.5 v, No. 2 batteries and an AC source. Various suitable motors that can be used in the present invention are commercially available on the market. Therefore, no detailed descriptions of the motor will be given here. 
         [0030]    Various connection mechanisms between ash container  10  and motor  14  can be used to removably attach motor  14  to the bottom of ash container  10 . 
         [0031]      FIG. 9  shows a shaft  16  according to the present invention. Both the upper end and the lower end of shaft  16  have a polygonal cross-section for engaging with the grill grid  2  and the rotating head  142  of motor  14 , respectively. When in use, the lower end of shaft  16  is inserted into and driven by the rotating head  142 . Shaft  16  has a fixed cylindrical block  161  restricted by two stops  163  at its two ends and a movable cylindrical block  162  at a lower portion of shaft  16 . Cylindrical block  162  can freely move along shaft  16  between stop  164  and stop  163 . The diameter of the fixed cylindrical block  161  and the movable cylindrical block  162  corresponds to the inner diameter of tube  106 . When assembled, both the fixed cylindrical block  161  and the movable cylindrical block  162  are inserted into tube  106  so as to align shaft  16  at an upright position. 
         [0032]      FIG. 10  shows a protection sleeve  18  used in the present invention. The inner diameter of protection sleeve  18  corresponds to the outer diameter of tube  106 . The protection sleeve  18  is placed over tube  106 . When assembled, one end of protection sleeve  18  is in contact with the bottom of Fire bowl  6 , the other end of protection sleeve  18  extends above fire grid  4 , but below grill grid  2 , to prevent ash from falling into tube  106  and rotating head  142 . 
         [0033]    Grill grid  2  has a center piece  201  with a center hole  202  for detachably receiving the upper end of shaft  16 . The center hole  202  has a size and cross-sectional shape corresponding to that of the upper end of shaft  16 , so that the upper end of shaft  16  can be inserted into the center hole  202  and drive grill grid  2  to rotate through the engagement between the center hole  202  of grill grid  2  and the upper end of shaft  16 . 
         [0034]    To support and position grill grid  2  and to facilitate the rotation of grill grid  2 , rotary supports  601  are provided on the upper edge of fire bowl  6 . As shown in  FIG. 11 , rotary support  601  includes a horizontally inward-extending shank  602  and a rotating sleeve  603  placed over shank  602 . Rotating sleeve  603  can rotate freely on shank  602 . Shank  602  is fixed to the sidewall of fire bowl  6  by nut  604  or by other means such as welding. When in use, the edge of grill grid  2  is supported by supports  601 . 
         [0035]    Fire grid  4  is placed in fire bowl  6  below grill grid  2  for holding charcoal. Charcoal ash falls into ash contained 10 through opening  605  at bottom of fire bowl  6 . 
         [0036]    If desirable, motor  14  can be removably attached to fire bowl  6  without ash container  10 . For example, connection piece  12  can be directly fixed to the bottom of fire bowl  6  and motor  14  is removably attached to connection piece  12 . In this case, air holes are provided on lower portion of fire bowl  6 . 
         [0037]    The present invention can be easily applied to various existing conventional charcoal barbecue grill by adding an ash container and a motor as described herein. 
         [0038]    The present invention has been described using exemplary embodiments. However, it is to be understood that the scope of the present invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangement or equivalents. The scope of the claims, therefore, should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and equivalents.