Patent Publication Number: US-7895997-B2

Title: Heating cooking appliance and burner system of the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority under 35 U.S.C. 119 and 35 U.S.C. 365 to Korean Patent Application No. 10-2006-0130607 (filed on Dec. 20, 2006), which is hereby incorporated by reference in its entirety. 
     BACKGROUND 
     The present disclosure relates to a heating cooking appliance, and more particularly, to a heating cooking appliance and a burner system of the same, which are configured to have a small size, achieve high burning efficiency, reduce air-flow resistance, and facilitate assembly thereof. 
     Heating cooking appliances are devices that cook food by heat. Particularly, a gas cooktop among the heating cooking appliances cooks food by heat generated through gas combustion. The cooktop is also called a hot plate or a hob, and is being increasingly used. 
     A burner system is employed in the cooktop operating by gas combustion. The burner system mixes a combustible gas with air to generate combustion. The burner system sprays a gaseous fuel through a nozzle, and introduces air together with the gaseous fuel into a mixing tube, using a decrease in air pressure around the sprayed gaseous fuel. A gas mixture introduced into a burner pot through the mixing tube is mixed again uniformly within the burner pot, and then combusts on a glow plate. Heat generated by the combustion is transferred to food by heat radiation and conduction to heat and cook the food. 
     To improve operational reliability of the burner system, the mixing tube, the nozzle and the burner pot must be precisely concentrically aligned, and the mixing tube and the nozzle must be installed and maintained at the same preset distance. If the components are not concentrically aligned or the distance between the components is different from the set value, the gas and air cannot be uniformly introduced, and the ratio of air to gas is reduced. This causes incomplete combustion, increasing emissions of carbon monoxide. 
     In the case of the general burner system, to meet the aforementioned requirements, the mixing tube is coupled to the burner pot, and the nozzle is firmly coupled to a case of a heating cooking appliance. 
     In order to improve user satisfaction and reduce material cost, heating cooking appliances are becoming more compact, and especially in the case of cooktops, compactness is essential to prevent a cooktop from protruding upward from a counter. 
     SUMMARY 
     Embodiments provide a heating cooking appliance and a burner system of the same, which can allow a nozzle and a mixing tube to be stably fixed even in a narrow heating cooking appliance, and can allow relative positions of components to be aligned with high precision. 
     Embodiments also provide a heating cooking appliance, and a burner system of the same, which can prevent misalignment of components and can allow a nozzle, a mixing tube, and a burner pot to be placed at preset positions with high precision by allowing an operator to easily align components of the burner system relative to one another. 
     In one aspect, a heating cooking appliance comprises: a case; a plate covering a top side of the case; a burner system in an internal space defined by the plate and the case; and an exhaust part at one edge of the plate, wherein the burner system includes: a nozzle unit provided with at least one nozzle to spray gas; a mixing tube unit provided with at least one mixing tube through which the gas and air are introduced, the mixing tube maintained a predetermined distance apart from the nozzle; a burner pot to uniformly mix the gas and air which are introduced through the mixing tube unit; a nozzle coupling part fixing a position of the nozzle; and a mixing tube coupling part fixing a position of the mixing tube. 
     In another aspect, a burner system comprises: a nozzle configured to spray gas; a mixing tube spaced apart from the nozzle to introduce the gas and air; a burner pot providing a mixing space in which the gas and air introduced through the mixing tube are uniformly mixed; a nozzle leg configured to fix a position of the nozzle; a mixing tube leg configured to fix a position of the mixing tube; and a coupling member to partially connect the nozzle leg with the mixing tube leg. 
     In a further aspect, a burner system comprises: a nozzle unit provided with at least one nozzle configured to spray gas; a mixing tube unit provided with at least one mixing tube apart from the nozzle to introduce air together with the gas therein; a burner pot providing a mixing space in which the gas and air introduced through the mixing tube unit are uniformly mixed; a nozzle coupling part configured to fix a position of the nozzle; a mixing tube coupling part configured to fix a position of the mixing tube; and a guide unit configured to align at least a part of the nozzle coupling part with at least a part of the mixing tube coupling part so that a relative positional relation between the nozzle unit and the mixing tube unit is precisely set. 
     Accordingly, the heating cooking appliance can be easily assembled, and components of the burner system can be precisely placed, so that the burner system can be stably and efficiently operated, and the components of the burner system can be placed at desired positions even when the heating cooking appliance has a compact structure. 
     The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a heating cooking appliance according to a first embodiment. 
         FIG. 2  is an exploded perspective view of a heating cooking appliance of  FIG. 1 . 
         FIG. 3  is a plan view of a heating cooking appliance of  FIG. 1 , excluding a ceramic plate. 
         FIG. 4  is a sectional view taken along line I-I′ of  FIG. 1 , illustrating a burner system according a first embodiment. 
         FIG. 5  is a perspective view of a burner system of  FIG. 4 . 
         FIG. 6  is a perspective view of a burner system according to a second embodiment. 
         FIG. 7  is a perspective view of a burner system according to a third embodiment. 
         FIG. 8  is an enlarged view of part A of  FIG. 7 . 
         FIG. 9  is a perspective view of a burner system according to a fourth embodiment. 
         FIG. 10  is a perspective view of a burner system according to a fifth embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. 
     Embodiment 1 
       FIG. 1  is a perspective view of a heating cooking appliance according to a first embodiment, and  FIG. 2  is an exploded perspective view of the heating cooking appliance of  FIG. 1 . 
     Referring to  FIGS. 1 and 2 , the heating cooking appliance includes a case  2 , a ceramic plate  1 , and a top frame  3 . The case  2  protects a lower side of a body, forms an entire bottom exterior of the heating cooking appliance, and is opened at a top side. The ceramic plate  1  is mounted on the top side of the case  2 , and the top frame  3  covers an edge portion of the ceramic plate  1 . A further exterior structure of the heating cooking appliances includes an exhaust grill  13  formed at the rear of the heating cooking appliance and serving to discharge exhaust gas, and at least one switch  14  formed roughly on the front side of the ceramic plate  1  and controlling ON/OFF of gas combustion. The exhaust grill  13  and the switch  14  may be variously implemented, but the construction of an exhaust unit for exhausting a combustion gas, and a switching unit for controlling ON/Off of gas combustion is necessary. 
     A plurality of components for gas combustion and gas exhaust, and control of the heating cooking appliance are received in an internal space defined by the case  2  and the ceramic plate  1 . This will now be described in detail. 
     In  FIG. 2 , three burner pots  4  are illustrated. Each burner pot  4  serves to mix the gas and the air enough to achieve uniform combustion. A mixing tube unit  6  is placed at a side surface of each burner pot  4  so that a gas mixture is supplied through the side surface of the burner pot  4 . A nozzle unit  5  is placed at a predetermined distance from an inlet of each mixing tube unit  6 , and serves to spray a gas toward the inlet of the mixing tube units  6 . 
     A burner frame  11  is placed on the burner pot  4 . The burner frame  11  supports the burner pot  4 , and provides an exhaust path of a combustion gas having combusted on a glow plate  12 . 
     An exhaust part  10  and the exhaust grill  13  are placed at the rear of the burner frame  11 . The exhaust part  10  and the exhaust grill  13  on the exhaust part  10  serve to exhaust the combustion gas to the outside. 
     The glow plate  12  on each burner pot  4  is heated by high-temperature heat generated when the gas mixture combusts. When the glow plate  12  is heated, radiation energy of a frequency band corresponding to a physical property of the glow plate  12 , preferably, a frequency band of infrared light, is emitted. The radiation energy of the glow plate  12  includes at least a frequency band of visible light, which allows a user to recognize that the heating cooking appliance is in operation. Of course, food is heated by radiation heat of the glow plate  12  and conduction heat of the ceramic plate  1 . 
     A structure of gas supply to the nozzle unit  5  will now be described. 
     A gas is supplied through a main gas supply tube  8  from the outside of the heating cooking appliance. A gas valve  7  controlled by the switch  14  controls the gas supply toward each burner system. The gas having passed through the gas valve  7  is supplied to the nozzle unit  5  through the gas supply tube  9 . 
       FIG. 3  is a plan view of the heating cooking appliance of  FIG. 1 . In  FIG. 3 , the ceramic plate  1  is excluded. 
     In  FIG. 3 , two of the burner pots  4  have relatively large sizes and are placed on both sides of the case  2 , and the remaining one has a relatively small size and is provided between the two relatively large burner pots  4 . Thus, a user may place a cooking container to be heated on one of the burner pots  4  according to heating values of the burner pots  4 . 
     In the relatively small burner pot  4  placed at the center of the case  2 , a gas mixture is mixed again while supplied from a front side toward a rear side of the burner pot  4 . After the gas mixture combusts on the glow plate  12 , the gas is exhausted rearwardly, that is, toward the exhaust part  10 . In the two relatively large burner pots  4  placed on both sides of the case  2 , a gas mixture is mixed again while supplied from a rear side toward a front side thereof. Then, the gas mixture combusts on the glow plate  12 , and is exhausted rearwardly of the burner pot  4 . 
     The disposition of the burner pots  4  is for implementing an optimum heating burner system. 
     The positioning of components within the heating cooking appliance can be easily observed through  FIG. 3 . 
     A burner system of the heating cooking appliance according to a first embodiment has a structure that allows stable flow of the gas and air while maintaining minimal heights of the burner system and the heating cooking appliance, can stably maintain a ratio of the air to the gas (hereinafter, referred to as an air ratio), and can ensure assemblability of the burner system. 
     The structure and operation of the burner system of the heating cooking appliance will now be described in detail. 
       FIG. 4  is a sectional view taken along line I-I′ o  FIG. 1 , illustrating a burner system according to a first embodiment.  FIG. 5  is a perspective view of the burner system of  FIG. 4 . 
     Referring to  FIG. 4 , the burner pot  4  is provided on the case  2 . The mixing tube unit  6  is disposed at a side surface of the burner pot  4 . The nozzle unit  5  is disposed adjacent to the inlet of the mixing tube unit  6  at a predetermined distance. 
     The operation of the burner system will now be described. A gas sprayed from the nozzle unit  5  is introduced into the mixing tube unit  6  at a high speed. The gas passes through the inlet of the mixing tube unit  6  at such a high speed that an adjacent space to the inlet of the mixing tube unit  6  becomes a low-pressure state according to Bernoulli&#39;s Theorem. Therefore, ambient air is introduced into the mixing tube  62  together with the gas, and thus a fluid passing through the mixing tube  62  becomes a gas mixture of the gas and air. The gas mixture having passed through the mixing tube unit  6  is introduced into an internal space of the burner pot  4  through an opening  42 , and is mixed again and combusts on the glow plate  12 . Combustion heat of the gas mixture heats the glow plate  12  to make the plate  12  red, and then radiation heat is generated from the glow plate  12 . 
     In order to introduce a maximum quantity of air when the gas sprayed from the nozzle unit  5  is introduced into the mixing tube unit  6 , it is important to concentrically align the nozzle unit  5  and the mixing tube unit  6  to maintain the distance between the nozzle  5  and the mixing tube unit  6 . Even though the nozzle unit  5  and the mixing tube unit  6  are designed to maintain the proper relative positional relation therebetween, this positional relation may be deviated during a manufacturing process or in use. If the positional relation is deviated, the amount of air being suctioned may decrease, flow resistance of the burner system may increase, and incomplete combustion may occur. 
     Therefore, a support structure is proposed, which allows the nozzle unit  5  and the mixing tube unit  6  to be placed at preset positions with high precision. 
     Referring to  FIG. 5 , the nozzle unit  5  includes a distribution tube  51  in which a gas flows, a nozzle holder  52  provided in front of the distribution tube  51 , and a plurality of nozzles  53  fixed on the nozzle holder  52  at regular intervals. Nozzle legs  54  extend from both end portions of the nozzle holder  52  toward the mixing tube unit  6 . The mixing tube unit  6  includes a plurality of mixing tubes  62 , a mixing tube support  61  supporting the mixing tubes  62 , and mixing tube legs  63  extending from both end portions of the mixing tube support  61  toward the nozzle unit  5 . Also, the burner pot  4  is placed in front of the mixing tube unit  6  as a separate component from the mixing tube unit  6 , and is coupled to the mixing tube support  61  by a separate coupling member such as a screw. 
     In such a burner system, the mixing tube unit  6  and the burner pot  4  may be aligned at desired positions by slightly inserting discharge ends of the mixing tubes  62  to the burner pot  4 . After this alignment, the burner pot  4  and the mixing tube unit  6  may be firmly coupled with each other by a separate coupling member such as a screw. Here, the mixing tube unit  6  is already in a state where the plurality of mixing tubes  62  are coupled to the mixing tube support  61 . 
     To align the mixing tube unit  6  and the nozzle unit  5  at desired positions, each mixing tube leg  63  includes a modification portion  64  at an end portion, and each nozzle leg  54  includes a corresponding modification portion  55  at an end portion, corresponding to the modification portion  64 . The modification portion  64  and the corresponding modification portion  55  each have modified parts from which modifications to respective original shapes of the legs  63  and  54  begin, and the modified parts contact each other, so that the nozzle unit  5  and the mixing tube unit  6  can be positioned at the desired positions with high precision. 
     The modification portion  64  and the corresponding modification portion  55  will now be described in more detail. For example, the modification portion  64  has a vertical height difference from an original shape of the mixing tube leg  63  by perpendicularly stepping the original shape of the mixing tube leg  63 . In more detail, the modification portion  64  is provided by stepping perpendicularly downwardly the original shape of the mixing tube leg  63 . The corresponding modification portion  55  corresponds to the modification portion  55 , and is provided by upwardly stepping an original shape of the nozzle leg  54 . When the modification portion  64  and the corresponding modification portion  55  are aligned at corresponding positions in a vertical direction, the stepped parts thereof contact each other, so that the mixing tube leg  63  and the nozzle leg  54  can be aligned vertically with high precision. 
     As mentioned above, the modification portion  64  and the corresponding modification portion  55  guide vertical relative placement of the mixing tube leg  63  and the nozzle leg  54  with high precision. Thus, from a functional perspective, the modification portion  63  and the corresponding modification portion  55  may be named vertical guides. 
     Of course, the mixing tube leg  63  and the nozzle leg  54  are automatically aligned in a forward and rear direction because of the respective height differences in the modification portion  64  and the corresponding modification portion  55 . When vertical and horizontal alignment is precisely made, the distance between the nozzle  53  and the inlet of the mixing tube  62  can be precisely set. 
     The modification portion  64  and the corresponding modification portion  55  can allow the legs  63  and  54  to be reliably and stably placed at the preset positions with high precision. Furthermore, the legs  63  and  54  also contribute to precisely aligning the relative positions between the nozzle  53  and the mixing tube  62 . For this reason, stable combustion performance of the burner system can be achieved, and stable performance of the mixing tube unit  6  and the nozzle unit  5  can be obtained despite compactness of the heating cooking appliance. Also, assembly of the mixing tube unit  6  and the nozzle unit  5  can be facilitated. Since the legs  63  and  54  are coupled so that the nozzle  53  and the mixing tube  62  are placed at the precise relative positions, the legs  63  and  54  can be named coupling parts. 
     After the modification portion  64  and the corresponding modification portion  55  precisely align the legs  63  and  54 , the nozzle unit  5  and the mixing tube unit  6  may be finally coupled with each other by inserting screws  69  into screw holes correspondingly formed in the respective legs  63  and  54 . The coupling of the legs  63  and  54  using the screws  69  may contribute to facilitating operations such as nozzle exchange or repair. The coupling method of the nozzle unit  5  and the mixing tube unit  6  is not limited to the insertion of the screws  69  into the screw holes, and various coupling methods such as rivet coupling, bolt-nut coupling, and coupling using clips may be employed provided that the coupling method allows separation between the nozzle unit  5  and the mixing tube unit  6  for repair to be performed later. 
     Embodiment 2 
       FIG. 6  is a perspective view of a burner system according to a second embodiment. The second embodiment is similar to the first embodiment. Therefore, description of the same parts of the second embodiment as the first embodiment will be omitted, and only differences therebetween will be described in detail. 
     Referring to  FIG. 6 , the mixing tube support  61  is formed integrally with the burner pot  4 . The mixing tube  62  may be fixed to the burner pot  4  by a screw insertion method. Even though the mixing tube  62  must be separately inserted into the burner pot  4 , the burner pot  4  and the mixing tube  62  can be precisely aligned. 
     As in the burner system according to the first embodiment, reliability of alignment according to the current embodiment can be improved by the legs  63  and  54  and the modification portions  64  and  55  when the nozzle unit  5  and the mixing tube unit  6  are coupled with each other. 
     Embodiment 3 
       FIG. 7  is a perspective view of a burner system according to a third embodiment, and  FIG. 8  is an enlarged view of part A of  FIG. 7 . The burner system according to the third embodiment is the same as that of the first embodiment, except for a modification portion and a corresponding modification portion. Thus, description of the same parts will be omitted, and only the difference between the burner systems of the first embodiment and the third embodiment will be described in detail. 
     Referring to  FIGS. 7 and 8 , a vertical modification portion  71  and a horizontal modification portion  72  correspond to the modification portion  64  of the first embodiment. A vertical corresponding modification portion  73  and a horizontal corresponding modification portion  74  correspond to the corresponding modified portion  55  of the first embodiment. In detail, the vertical modification portion  71  is formed similarly to the modification portion  64  of the first embodiment, and the vertical corresponding modification portion  73  is formed similarly to the corresponding modification portion  55  of the first embodiment. Thus, the legs  63  and  54  according to the third embodiment can guide relative positions of the mixing tube unit  6  and the nozzle unit  5  in a vertical direction. 
     According to the third embodiment, when the legs  63  and  54  are aligned with each other, the horizontal modification portion  72  and the horizontal corresponding modification portion  74  contact each other, thereby stopping and supporting the legs  63  and  54  at the contacting position. Accordingly, the legs  63  and  54  can stably guide the relative positions of the mixing tube unit  6  and the nozzle unit  5  in a horizontal direction. 
     Since the alignment of the legs  63  and  54  is guided in a vertical direction, in a forward and rearward direction, and in a left and right direction, the mounting process of the legs  63  and  54  is facilitated, and reliability of the alignment of the nozzle  53  and the mixing tube  62  can be improved. Of course, in the current embodiment, the nozzle unit  5  can be separated from the mixing tube unit  6  by lifting up the nozzle unit  5 . 
     Embodiment 4 
       FIG. 9  is a perspective view of a burner system according to a fourth embodiment. The fourth embodiment is the same as the first embodiment, except for a modification portion and a corresponding modification portion, and thus description of the same parts of the current embodiment as those in the first embodiment will be omitted, and only the difference therebetween will be described in detail. 
     Referring to  FIG. 9 , a modification portion  81  is formed by recessing any one of the legs  63  and  54  in the form of a groove or hole, and a corresponding modification portion  82  is formed on the other leg in the form of a protrusion. 
     A base portion of the modification portion  81  where the recessing begins may have a shape fitting in at least a base portion of the corresponding modification portion  82 . Thus, when the pair of legs  63  and  54  is aligned, they can be placed at preset positions with high precision. 
     Since the rounded shapes are provided according to the current embodiment, there is no need to additionally provide the vertical modification portion and the horizontal modification portion according to the third embodiment. Accordingly, the rounded shapes allow the legs  63  and  54  to be conveniently aligned in every movement direction, that is, in a forward and rearward direction, a vertical direction, and a left and right direction. 
     Embodiment 5 
       FIG. 10  is a perspective view of a burner system according to a fifth embodiment. The fifth embodiment is the same as the first embodiment, except for the number of mixing tubes and the nozzle. Therefore, description of the same parts of the fifth embodiment as those in the first embodiment will be omitted, and only the difference therebetween will be described in detail. 
     Referring to  FIG. 10 , one mixing tube  62  and one nozzle  53  are provided according to the current embodiment. To align the mixing tube  62  and the nozzle  53  with each other with high precision, legs  63  extend from both sides of the mixing tube  62 , and legs  54  extend from the nozzle holder  5  to face the respective legs  63  of the mixing tube  62 . Of course, a modification portion and a corresponding modification portion are formed in the same manner as described in the previous embodiment. 
     Accordingly, the relative positions of the mixing tube  62  and the nozzle  53  can be aligned with high precision. 
     Embodiments are not limited to the aforementioned embodiments, the following embodiments may be further provided. 
     Although the nozzle legs and the mixing tube legs are respectively provided in pairs in the aforementioned embodiments, one nozzle leg and one mixing tube leg may be provided, or three or more nozzle legs and three or more mixture pip legs may be provided. One leg may be provided when one opening and one mixing tube are provided, but if one leg is provided in the case where a plurality nozzles and a plurality of mixing tubes are respectively provided for the nozzle unit and the mixing tube unit, the alignment may become difficult. When three or more nozzles and three or more mixing tubes are provided, three or more legs are provided to improve reliability of the alignment between the nozzle unit and the mixing tube unit. 
     Although the modification portion and the corresponding modification portion are respectively formed in bar-shaped legs of the nozzle unit and the mixing tube unit extending to face each other in the aforementioned embodiments, the modification portion and the corresponding modification portion may be respectively provided in plate-shaped parts corresponding to each other, or may be respectively provided in any portions that widely expand from respective ends of the legs. Any portion extending from any member fixed to the mixing tube and any portion extending from any member fixed to the nozzle may be modified at a position where the portions overlap each other, and be aligned with each other, so that the functions of the modification portion and the corresponding modification portion can be performed. 
     Although the legs extend to face each other from a lower side of the mixing tube support to which a plurality of mixing tubes are aligned and fixed, and from a lower of the nozzle holder to which a plurality of nozzles are fixed in the aforementioned embodiments, the legs may directly extend from the mixing tube, and may directly extend from the nozzle by modifying the nozzle or may extend from the a distribution tube. Particularly, in the case where one mixing tube and one nozzle are formed, a mixing tube leg extending from the mixing tube may be considered convenient. Of course, convenience is improved when the legs extend from the mixing tube support and the nozzle holder to face each other with regard to factors associated with a distance and convenient manufacturing. 
     The modification portion and the corresponding modification portion are described as portions formed by modifying original shapes of the legs for convenient coupling of the legs. 
     According to embodiments, even if a heating cooking appliance includes a narrow internal space, a nozzle and a mixing tube can be stably fixed, and relative positions of components of the heating cooking appliance can be precisely aligned, thereby improving operational reliability of the heating cooking appliance. 
     Also, an operator can easily assemble the burner system so that the components are prevented from being mistakenly misaligned, and a nozzle, a mixing tube and a burner pot can be placed at preset positions with high precision. 
     For example, when the nozzle needs to be repaired, the nozzle unit can be separated just by unfastening a coupling member such as a screw, and the nozzle unit can be coupled precisely at a desired position after being repaired. 
     Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments. 
     Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.