Abstract:
A chafing dish includes a pan, a cover hingedly connected to the pan through a hinge shaft, a plurality of cover arms, each cover arm having one end secured to the hinge shaft and other end to the cover, and a counter balance member which encircles a part of the hinge shaft and is secured in position at both ends in a hinge assembly, thereby enabling the counter balancing of the cover at any angle from the closed state of the cover.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to India Patent Application No. 1693/DEL/2011, filed on Jun. 14, 2011. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Technical Field 
         [0003]    This invention relates generally to the field of chafing dishes typically for buffet type serving used by restaurant and banquet facilities. The invention more specifically relates to hinged covered dishes to provide a stably held open cover up to approximately 90 degree without any supports. 
         [0004]    2. Background 
         [0005]    It is well known in the art to provide chafing dishes having a container for serving food. Chafing dishes are typically used on portable heating devices such as induction stoves, propane stoves, and alcohol gel fueled grills. Conventional chafing dishes used in the catering industry have a number of limitations. A problem associated with the conventional chafing dishes is the horizontal force generated when the cover is opened, which can move the chafer off the stove. Thus, there is a need for developing a means of securing the chafer to the stove. 
         [0006]    Further, conventional chafing dishes use friction pads to maintain the chosen open position of the cover during use. Some chafing dishes use rubbery type friction pads, adjusted so that the cover slowly closes during use. 
         [0007]    Another problem with the conventional chafers is that the friction pads wear off with use which loosens the set up causing the covers to fall closed. 
         [0008]    Therefore, there is a need for a chafing dish that overcomes the above and other shortcomings present in current chafing dishes. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    According to one embodiment of the present invention, a chafing dish comprises: a pan; a cover; a hinge shaft coupled to the pan and the cover; a first cover arm coupled to a first end of the hinge shaft and to the cover; a second cover arm coupled to a second end of the hinge shaft and to the cover; a counter balance member encircling a part of the hinge shaft; and a hinge assembly coupled to a first end and a second end of the counter balance member, the counter balance member having a torsion enabling a counter balancing of the cover at any angle from a closed state to an unstressed state. 
         [0010]    In one aspect of the present invention, the chafing dish comprises an externally adjustable balance adjustment mechanism coupled proximately to the first end of the hinge shaft, comprising a bearing support for the hinge shaft, the bearing support comprising a balance adjuster and a stop adjuster protruding through end caps of the hinge assembly, whereby allowing adjustment of the chafing dish without disassembly. 
         [0011]    In one aspect of the present invention, a first end of the first cover arm is coupled to the hinge shaft through fasteners, wherein a second end of the first cover arm is welded to the cover. 
         [0012]    In one aspect of the present invention, the fasteners comprise thumb screws. 
         [0013]    In one aspect of the present invention, the counter balance member comprises a torsion spring encircling the part of the hinge shaft. 
         [0014]    In one aspect of the present invention, the first end of the counter balance member is coupled to a balance adjuster and the second end of the counter balance member is coupled to a shaft anchor. 
         [0015]    In one aspect of the present invention, the pan comprises a water pan. 
         [0016]    In one aspect of the present invention, the chafing dish further comprises a food pan nested inside the water pan. 
         [0017]    In one aspect of the present invention, the chafing dish further comprises a condensate drain tube coupled to the cover and a condensate catch trough coupled to the pan, wherein condensate from the cover is able to drain from the condensate drain tube to the pan through the condensate catch trough. 
         [0018]    In one aspect of the present invention, the chafing dish further comprises a cover handle for raising and lowering the cover. 
         [0019]    In one aspect of the present invention, the chafing dish further comprises a balance adjuster and a stop adjuster for supporting the hinge shaft. 
         [0020]    In one aspect of the present invention, the chafing dish further comprises: a balance set screw for holding a position of the stop adjuster; and a stop set screw for holding a position of the balance adjuster. 
         [0021]    In one aspect of the present invention, the chafing dish further comprises a shaft stop and a stop adjuster pin for limiting an opening of the cover to the unstressed state of the counter balance member. 
         [0022]    In one aspect of the present invention, the chafing dish further comprises a hinge support frame coupled to the hinge assembly and the pan. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE FIGURES 
         [0023]    The aforementioned aspects and other features of the present invention will be explained in the following description, taken in conjunction with the accompanying drawings, wherein: 
           [0024]      FIG. 1  illustrates a front view of a chafing dish in accordance with one embodiment of the present invention. 
           [0025]      FIG. 2  illustrates a side view of the chafing dish of  FIG. 1  in accordance with one embodiment of the present invention. 
           [0026]      FIG. 3  illustrates a top view of the chafing dish of  FIG. 1  in accordance with one embodiment of the present invention. 
           [0027]      FIG. 4  illustrates a perspective view of the chafing dish of  FIG. 1  depicting a cover in altered relative position in accordance with one embodiment of the present invention. 
           [0028]      FIG. 5  illustrates a cross-sectional view of a hinge assembly of the chafing dish as seen from the plane  5 - 5  in  FIG. 3  in accordance with one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    One embodiment of the present invention provides a chafing dish ( 10 ), which employs a spring ( 46 ) to counterbalance a cover ( 13 ) and which further employs an externally adjustable balance adjustment mechanism. The spring based mechanism which is used to counterbalance the cover ( 13 ) permits smooth opening and closing of the cover of the chafing dish without generation of any horizontal force when the cover ( 13 ) is opened, thereby reducing the risk of the chafing dish ( 10 ) from falling off the stoves on which they are placed. 
         [0030]    Further, the embodiment of the chafer dish of the present invention is more user friendly and the cover can be stably held open at any angle up to 90 degrees from the cover&#39;s closed state, without any support. Also, the use of externally adjustable balance adjustment mechanism permits accurate balancing without the need to disassemble and reassemble the spring loaded hinge. This allows the user to easily replace and rebalance different design covers which may be otherwise inconvenient to use. 
         [0031]    The embodiments of the present invention are described in detail with reference to the accompanying drawings. However, the present invention is not limited to these embodiments which are only provided to explain more clearly the present invention to the ordinarily skilled in the art. In the accompanying drawings, like reference numerals are used to indicate like components. 
         [0032]    Referring to  FIG. 1  &amp;  FIG. 2 , it can be seen that the chafing dish  10  of one embodiment of the present invention includes a water pan  11 , a food pan  12 , a cover  13 , and a hinge assembly  15 . The food pan  12  ( FIG. 4 ), nests inside the water pan  11 , with the top flange of the food pan  12  resting on the water pan  11 . Referring to  FIG. 3 , the cover  13  is connected to the hinge shaft  17  by the cover arms  19 , and secured using thumb screws  18 . The cover  13  is raised and lowered using a cover handle  14 . When the cover  13  is raised, condensate formed while heating food in the food pan  12  drains through the condensate drain tube  21  ( FIG. 2 ), into the condensate catch trough  22 , which drains into the water pan  11  through a hole in the water pan  11  (not shown). The hinge assembly  15  ( FIG. 2 ) is welded to the hinge support frame  20 , which is further welded to the water pan  11 . 
         [0033]    Referring to  FIG. 5 , it can be seen that end caps  31  are attached to the hinge barrel  30  with screws. The balance adjuster  40 , and stop adjuster  50  are bearing supports for the hinge shaft  17 , and protrude through the end caps  31 , thereby making these accessible for external adjustment. Balance set screw  41 , and stop set screw  51  lock these adjusters in place. 
         [0034]    The counterbalance spring  46  has one end placed in the balance adjuster anchor hole  43  and the other end placed in the shaft anchor hole  45 . As can be seen from  FIG. 5 , the counter balance spring  46  encircles the hinge shaft  17 . In one embodiment of the present invention, the counter balance spring  46  is a counterclockwise torsion spring, which is chosen so that when operated from unstressed position to approximately 90 degrees rotation (the closed position), its torque is approximately equal to the torque required to raise the closed cover through the full range of angles from the closed position to the unstressed position. 
       Adjustment Operation 
       [0035]    To adjust the full open cover position, referring to  FIG. 5 , the stop set screw  51  is released. While holding the cover open at 90 degrees to the closed position of  FIG. 2 , the stop adjuster  50  is rotated clockwise with a spanner wrench in stop spanner wrench holes  52 , until the stop adjuster  50  stops. The stop set screw  51  is then tightened. When the cover  13  is opened by 90 degrees, the shaft stop  54  contacts the stop adjuster pin  55 , thereby preventing further opening. 
         [0036]    To adjust the counterbalance of the cover  13  (referring to  FIG. 5 ), while holding the cover  13  at 90 degrees (as set in the previous paragraph), the balance set screw  41  is released and retightened. This is done to release any tension in the counter balance spring  46 , and to set the trial spring tension. 
         [0037]    The cover  13  is closed to test the counterbalance adjustment. If the cover  13  moves up from the food pan  12 , the counter balance spring  46  is too tight. If the cover  13  falls when released while closing, the counter balance spring  13  is not tight enough. To further adjust the spring balance, the cover  13  is opened to the 90 degree position, which relieves torsion from the counter balance spring  46 . The balance set screw  41  is released and the balance adjuster  40  is turned slightly with a spanner wrench in balance spanner wrench holes  42 . If the counter balance spring  46  is too tight, the balance adjuster  40  is moved clockwise. If the counter balance spring  46  is too loose, the balance adjuster  40  is moved counterclockwise. The balance set screw  41  is then tightened. 
         [0038]    Once a particular style of cover is balanced, a line can be inscribed on the balance adjuster and end cap, and labeled with the cover style. Different style covers can then be quickly adjusted. 
         [0039]    Although the subject matter has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the subject matter, will become apparent to persons skilled in the art upon reference to the description of the subject matter. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present subject matter as defined.