Patent Publication Number: US-8122875-B2

Title: Burner assembly for gas burners of radiant heating type

Description:
TECHNICAL FIELD 
     The present invention relates to gas burners of radiant heating type, and more particularly, to a burner assembly for gas burners of radiant heating type, in which a burner mat is made to have a non-combusting area for enabling uniform combustion throughout the burner mat even if a flow rate of mixed gas is low. 
     BACKGROUND ART 
     The present invention relates to gas burners of radiant heating type, and more particularly, to a burner assembly therefore. In general, the gas burner of radiant heating type is a range in which a heating object is heated with a radiant wave emitted from a radiant body when the radiant body is heated by burning a mixed gas of a fuel and air, to cook food. 
       FIG. 1  illustrates a related art gas burner of radiant heating type, schematically. That is, the related art gas burner of radiant heating type is provided with an oven part  10 , and a top burner part  20 . 
     The top burner part  20  is provided with a burner assembly shown in  FIG. 2 . The related art burner assembly will be described with reference to  FIG. 2 . 
     The related art burner assembly is provided with a burner housing  21 , a glass plate  22 , a mixing tube  23 , a burner chamber  24 , and a burner mat  25 . The burner housing  21  shapes an outside of the burner assembly, and forms a combustion space. The glass plate  22  is placed on top of the burner housing  21  to close an upper part of the burner assembly. 
     The mixing tube  23  is a tube in which fuel and air are introduced therein and mixed together, and is in communication with the burner chamber  24 . The burner chamber  24  has a closed circumference and an opened top, for receiving the mixed gas from the mixing tube  23 , and storing the mixed gas therein. The opened top of the burner chamber  24  is in communication with an inside space of the burner housing  21 . 
     The burner mat  25  is placed on the burner chamber  24 , for burning the mixed gas from the burner chamber  24 . The burner mat  25  makes surface combustion of the mixed gas, and serves as a radiant body for emitting a radiant wave. 
     The operation of the burner assembly will be described. 
     When a user ignites in a state a heating object is placed on the glass plate  22 , the fuel and air are introduced into the mixing tube  23 , and mixed therein during the fuel and air pass through the mixing tube  23 . 
     Then. the mixed gas is introduced into the burner chamber  24  in communication with the mixing tube  23 , passes through the burner mat  25 , and blows out into the inside of the combustion space of the burner housing  21 . At the same time with this, the mixed gas is ignited with an igniting spark generated by an igniting means (not shown). 
     The mixed gas burns on a surface of the burner mat  25 , and the burner mat  25  emits a radiant wave as the burner mat  25  is heated by the combustion. Then, the radiant wave transmits the glass plate  22 , and heats the heating object, to cook food. 
     However, the related art burner assembly has a problem in that a low temperature heating is difficult in a case the burner assembly is a relatively large size application, for example, not for heating of a small kettle, but for heating of a large cooking object. 
     That is, in a case the gas supply is reduced for low temperature heating, to cause an extreme shortage of the mixed gas supplied to the burner chamber  24  compared to an area of the burner mat  25 , the combustion takes place only in a central part of the burner mat  25  the mixed gas supply thereto is smooth, but not in an outer part of the burner mat  25 . 
     Thus, if the combustion takes place only in the central part of the burner mat  25 , but not in the outer part of the burner mat  25 , the large cooking object will be heated at the central part, but not throughout the large cooking object, uniformly. 
     Moreover, when the combustion takes place only at the central part of the burner mat  25  locally, the flame can be extinguished, easily. This is because, taking a substantially large surface area of the burner mat  25  into account, the flame at the central part of the burner mat  25  can not spread to the outer part of the burner mat  25  smoothly due to shortage of the mixed gas. In this case, the gas keeps flow out even if there is no combustion, to cause fire hazard. 
     DISCLOSURE OF INVENTION 
     An object of the present invention designed to solve the foregoing problems lies on providing a burner assembly which enables smooth combustion at an outer part of a burner mat too, even if supply of mixed gas is small. 
     The object of the present invention can be achieved by providing a burner assembly for a gas burner of radiant heating type including a burner chamber for receiving mixed gas, a burner mat on a top of the burner chamber having a combusting area, and at least one non-combusting area, and a combustion cutoff part for forming the non-combusting area of the burner mat. 
     The combustion cutoff part includes a structure for forming the non-combusting area between a center and an outer part of the burner mat, or at a center part of the burner mat, including a cutoff plate in close contact with an upper surface or a lower surface of the burner mat for preventing the mixed gas from reaching to a surface of the burner mat, and burning, and a supporting part for supporting the cutoff plate. 
     In other aspect of the present invention, there is provided a burner assembly for a gas burner of radiant heating type including a burner chamber for receiving mixed gas, and a burner mat part on top of the burner chamber, including an inner burner mat and an outer burner mat each having a combusting area, and a separated part between the inner burner mat and the outer burner mat having a non-combusting area. 
     The separated part between respective burner mats includes a cutoff plate in close contact with a circumference of an upper surface of each of the burner mats, and a supporting part connected to the cutoff plate having seating steps for seating the circumference of each of the burner mats. 
     In another aspect of the present invention, there is provided a burner assembly for a gas burner of radiant heating type including a burner chamber for receiving mixed gas, and a burner mat on top of the burner chamber having a combusting area for making combustion, and at least one non-combusting area for making no combustion. 
     The non-combusting area of the burner mat is formed of a material that permits no surface combustion different from the combusting area. 
     Thus, the burner assembly of the present invention can make stable combustion only with a low flow rate of mixed gas to improve a combusting efficiency, while a heating performance is not dropped, by forming an overall size of the burner mat large adequately, while a part the mixed gas is supplied thereto and burned is formed smaller. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. 
       In the drawings; 
         FIG. 1  illustrates a perspective view of an outside appearance of a related art gas burner of radiant heating type; 
         FIG. 2  illustrates a section showing key parts of a related art burner assembly for a gas burner of radiant heating type, schematically; 
         FIG. 3  illustrates a section showing key parts of a burner assembly for a gas burner of radiant heating type in accordance with a preferred embodiment of the present invention, schematically; 
         FIGS. 4A˜4D  illustrate plan views each showing an example of a form of a cutoff plate, and a fitting state of the cutoff plate to a burner mat in accordance with a first preferred embodiment of the present invention; 
         FIG. 5  illustrates a section showing an example of a cutoff plate in accordance with a first preferred embodiment of the present invention fitted to a bottom of a burner mat closely; 
         FIG. 6  illustrates a plan view of a burner mat in accordance with a first preferred embodiment of the present invention; 
         FIG. 7  illustrates a section showing another example of a cutoff plate in accordance with a first preferred embodiment of the present invention fitted to a bottom of a burner mat closely; 
         FIG. 8  illustrates a section of a burner assembly in accordance with a second preferred embodiment of the present invention, schematically; 
         FIG. 9  illustrates a section of a variation of a burner assembly in accordance with a second preferred embodiment of the present invention, schematically; 
         FIG. 10  illustrates a section of a burner assembly in accordance with a third preferred embodiment of the present invention, schematically; 
         FIGS. 11A and 11B  illustrate plan views each showing an example of a form of a cutoff plate, and a fitting state of the cutoff plate to a burner mat in accordance with a third preferred embodiment of the present invention; and 
         FIG. 12  illustrates a plan view of a burner mat in accordance with a fourth preferred embodiment of the present invention, schematically. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
     The burner assembly in accordance with a first preferred embodiment of the present invention includes a burner chamber  140 , a burner mat  150 , and a combustion cutoff part. The burner chamber  140  is mounted on an underside of the burner housing  110  for receiving a mixed gas mixed at the mixing tube  130 . The burner chamber  140  has an opened top. The burner chamber  140  may have a shape the same with the related art as shown in the drawing, or modified similar thereto. 
     The burner mat  150  is placed on top of the burner chamber  140 , and has a combusting area, and at least one non-combusting area. The non-combusting area is an area fabricated to burn gas, but made unable to make the surface combustion by means of other structure. 
     The combustion cutoff part forms the non-combusting area at the burner mat  150 . The combustion cutoff part includes a cutoff plate  161  for forming the non-combusting area between a center and an edge of the burner mat  150 . 
     The cutoff plate  161  is brought into close contact with at least one of upper surface and lower surface of the burner mat  150 , for preventing the mixed gas from reaching to a surface of the burner mat  150 . Particularly, it is preferable that the cutoff plate  161  has a ring form substantially when seen in a plan view. 
     The ring form may be circular as shown in  FIG. 4A , or, though not shown, polygonal, such as square, pentagonal, hexagonal and the like. The cutoff plate  161  may not be a ring form, but spiral as shown in  FIG. 4B , radial extensions as shown in  FIG. 4C , or has a form that becomes the wider (or narrower) as it goes to an edge from the center of the burner mat  150 . 
     It is preferable that the cutoff plate  161  can maintain a state in which the cutoff plate  161  is in close contact with a surface of the burner mat  150 , for which the combustion cutoff part in accordance with the preferred embodiment of the present invention further includes a supporting part  162 . 
     The supporting plate  162  supports the cutoff plate  161  such that the cutoff plate  161  is maintained the state in which the cutoff plate  161  is in close contact with the burner mat  150 . As shown, in the case the cutoff plate  161  has a structure in which the cutoff plate  161 , is in close contact with the lower surface of the burner mat  150 , the supporting part  162  has one end fixed to an inside bottom of the burner chamber  140 , and the other end supporting a lower surface of the cutoff plate  161 . 
     Referring to  FIG. 5 , if the cutoff plate  161  has a structure in which the cutoff plate  161  is in close contact with the upper surface of the burner mat  150 , the supporting part  162  has one end fixed to an inside bottom of the burner chamber  140 , and the other end passed through the burner mat  150  and connected to the cutoff plate  161 . 
     Though the part of the burner mat  150  having the other end of the supporting part  162  passed therethrough may has a form of a ring the same with the cutoff plate  161 , which divides the burner mat  150  into two parts, as shown in  FIG. 6 , it is more preferable that a plurality of through holes  151  are formed in parts of the burner mat  150  for passing the supporting part. 
     Moreover, it is preferable that the other end of the supporting part  162  is fastened to the cutoff plate  161  with screws  162   a , for smooth fitting. However, the other end of the supporting part  162  may be joined with the cutoff plate  161  by welding of other joining structure. 
     Furthermore, in a case of above structure, there is a problem in that gas can be leaked through a connection part between the other end of the supporting part  162  and the cutoff plate  161 . 
     Accordingly, as shown, it is more preferable that a sealing member  163  is provided between a connection part of the supporting part  162  and the cutoff plate  161 , for preventing leaking of the mixed gas from the burner chamber  140 . It is preferable that the sealing member  163  is formed of a non-combustible material. 
     Moreover, it is preferable that the cutoff plate  161  is greater than opened parts having the supporting part  162  of the burner mat  150  passed there through, and the sealing member  163  is greater than the cutoff plate  161 . 
     Of course, as described before, if the cutoff plate  161  has a structure in which the cutoff plate  161  is in close contact with the upper surface of the burner mat  150 , the supporting part  162  may not pass through the burner mat  150  as shown in  FIG. 7 . 
     In this case too, it is preferable that the sealing member  163  is provided between the cutoff plate  161  and the upper surface of the burner mat  150 , and it is preferable that the cutoff plate  161  is fastened to the supporting part  162  with screws  162   a.    
     Moreover, it is preferable that, by providing openings in a side surface (circumferential surface) of the supporting part  162 , the mixed gas flows from the burner chamber  140  to the outer side of the burner mat  150 , smoothly. Particularly, it is more preferable that, by providing the supporting part  162  of mesh form, the mixed gas spreads more smoothly. 
     For an example, if the supporting part  162  is of a cylindrical mesh form, with a bottom part thereof in communication with the mixing tube  130 , since the mixed gas introduced into the burner chamber  140  from the mixing tube  130  can spread to an outer side space inside of the burner chamber  140  in a process the mixed gas passes through the supporting part  162 , concentration of the combustion only to the central part of the burner mat  150  can be prevented. Of course, as shown, it is more preferable that only a part of side of the supporting part  162  is of the mesh form for solving a problem of strength. 
     A burning process of the burner assembly having the system of the first preferred embodiment of the present invention applied thereto will be described. 
     When the user ignites, gas and air are introduced into the mixing tube  130 , and mixed during the gas and the air pass through the mixing tube  130 . The mixed gas is introduced into the burner chamber  140  that is in communication with the mixing tube  130 , and blows out into the combustion space of the burner housing  110  through the burner mat  150 . At the same time with this, the mixed gas is ignited by an igniting spark generated with igniting means (not shown). 
     In this instance, the mixed gas can not reach to a part of a surface of the burner mat  150  to which the cutoff plate  161  is in close contact thereto. Consequently, the mixed gas flows toward a neighborhood of the part to which the cutoff plate  161  is in close contact thereto. Since a mixed gas flow toward the central part of the burner mat  150  is smooth, the mixed gas flows toward the neighborhood and flows toward the outer side part of the burner mat  150 . Especially, the supporting part  162 , supporting the cutoff plate  161 , serves to guide the gas to flow toward the outer side of the burner mat  150  additionally, which permits a uniform surface combustion throughout entire part of the burner mat  150 . 
     Of course, the non-combusting area of the burner mat  150 , in which no combustion is made to take place by the cutoff plate  161 , is heated to a high temperature, even though there is no actual combustion of the mixed gas taken place thereon, because the heat of combustion at the central part and the outer side of the burner mat  150  circulates therethrough. 
     The radiant wave from the surface combustion of the burner mat  150  transmits the glass plate  120 , and heats the heating object, to heat even a large cooking container uniformly throughout an entire part thereof. 
       FIG. 8  illustrates a section of a burner assembly in accordance with a second preferred embodiment of the present invention, schematically. 
     Referring to  FIG. 8 , the burner assembly is suggested to have an inner burner mat  251  and an outer burner mat  252 , separate from each other. A separated part between the inner burner mat  251  and the outer burner mat  252  forms a non-combusting area, while the inner and outer burner mats form combusting area. 
     It is preferable that a combustion cutoff part is provided in the separated part between the inner burner mat  251  and the outer burner mat  252 . The combustion cutoff part serves to support the burner mats  251  and  252  stably, and forms the non-combusting area. 
     For this, the combustion cutoff part includes a cutoff plate  261  in close contact with a circumference of an upper surface of each of the burner mats  251  and  252 , and a supporting part  262  connected to the cutoff plate  261 , having seating steps  262   b  for seating a circumference of each of the burner mats  251  and  252 . 
     It is preferable that the cutoff plate  261  is fasted to the supporting part  262  with screws  262   a , and it is more preferable that a sealing member  263  is provided between the cutoff plate  261  and the supporting part  262 , for preventing leakage of the mixed gas from the burner chamber  140 . 
       FIG. 9  illustrates a section of a variation of a burner assembly in accordance with a second preferred embodiment of the present invention, schematically. 
     The variation of a burner assembly in accordance with a second preferred embodiment of the present invention includes an inner burner mat  251  and an outer burner mat  252 , and a connecting member  264  for connecting the inner mat  251  and the outer mat  252 . The connecting member  264  connects the separated burner mats  251  and  252 , as well as surrounds connected parts of the burner mats  251  and  252 . Especially, opposite edges of the connecting member  264  are recess for receiving the connected parts of the burner mats  251  and  252 . 
     The connecting member  264 , not only permits stable supporting of the separated burner mats  251  and  252 , but also forms the non-combusting area by cutting off the mixed gas supply to the part, without any additional cutoff plate  261  or the supporting part  261 . 
     The operation of the burner assembly in accordance with the second embodiment of the present invention is the same with the operation of the first embodiment of the present invention. That is, while no combustion takes place in the separated part between the burner mats  251  and  252 , stable combustion takes place not only on the inner burner mat  251 , but also on the outer burner mat  252  owing to the smooth flow of the mixed gas to neighborhood of the part the cutoff plate  261  or the connecting member  264  is provided thereto, permitting to heat even a comparatively large cooking container throughout entire surface. 
       FIG. 10  illustrates a section of a burner assembly in accordance with a third preferred embodiment of the present invention, schematically. 
     The burner assembly in accordance with a third preferred embodiment of the present invention includes a combusting cutoff part in a central part of the burner mat  350  for cutting off surface combustion. The combusting cutoff part includes a cutoff plate  361  in contact with the central part of an upper surface or a lower surface of the burner mat  350 . 
     The cutoff plate  361  prevents the mixed gas flowing in the burner chamber  140  from reaching to a surface of the central part of the burner mat  350 , to prevent surface combustion from taking place in the central part of the burner mat  350 . 
     It is preferable that the combusting cutoff part further includes a supporting part  362  for stable supporting of the cutoff plate  361 . The cutoff plate  361  may be a disc as shown in  FIG. 11A , or polygonal as shown in  FIG. 11B  when seen in a plan view. Of course, though not shown, the cutoff plate  361  may be of a mesh form. 
     In a case the cutoff plate  361  has a structure in which the cutoff plate  361  is in close contact with a lower surface of the burner mat  350 , the supporting part  362  has one end fixed to an upper surface of an inside of the burner chamber  140 , and the other end formed to support a lower surface of the cutoff plate  361 . It is preferable that the supporting part is cylindrical, with openings in a circumferential surface thereof for discharging the mixed gas. Particularly, it is more preferable that the circumferential surface of the supporting part  362  is of the mesh form. Of course, though not shown, the supporting part  362  may be in a form of a bar, simply. 
     The structure of the burner assembly in accordance with a third embodiment of the present invention enables uniform heating of a comparatively large cooking container throughout entire part, as combustion of the mixed gas is made to take place even in the outer side part of the burner mat  350  even with a low flow rate of mixed gas by forming a non-combusting area in a center part of the burner mat  350 , and a combusting area in the outer side part of the burner mat  350 . 
       FIG. 12  illustrates a plan view of a burner mat in accordance with a fourth preferred embodiment of the present invention, schematically. 
     It is suggested that the burner assembly in accordance with a fourth preferred embodiment of the present invention includes a burner mat  450  having a combusting area for combusting a gas, as well as at least one non-combusting area for making no combustion therein. 
     That is, different from either of the first to third embodiments, the burner mat  450  in accordance with a fourth preferred embodiment of the present invention has no combustion cutoff part separately, but the burner mat  450  itself has the non-combusting area. 
     For this, the present invention suggests that the non-combusting area of the burner mat is formed of a material different from the combusting area. That is, the non-combusting area of the burner mat  450  is formed of a material  451  that permits no surface combustion. 
     As shown in the drawing, the non-combusting area of the material may be formed between the center and the outer side of the burner mat  450 , or at the center part of the burner mat  450 . 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. 
     INDUSTRIAL APPLICABILITY 
     The burner assembly of the present invention permits uniform heating of a comparatively large container throughout entire part thereof even at a low temperature, because combustion can take place even at the outer side of the burner mat even if a flow rate of mixed gas is low. 
     Moreover, the availability of the uniform combustion throughout the entire part of the burner mat resolves the related art problem in which the flame is extinguished easily.