JP2013178006A - Rich/lean combustion burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rich/lean combustion burner capable of unifying a supply flow rate of rich air-fuel mixture over all longitudinal direction regions when rich air-fuel mixture in a rich air-fuel mixture introduction passage is introduced into a rich air-fuel mixture supply passage from a communication hole at a longitudinal direction intermediate position and the rich air-fuel mixture is supplied to a central rich flame hole.SOLUTION: Rich flame holes 331 at a central rich burner part 3a, lean flame holes of lean burner parts at both sides and rich flame holes of outer rich burners at both outer sides are arrayed in order. A lower end part 60a of the central rich burner part is protruded to open a first communication hole 61 in relation to the inside of a cylinder part 38 into which rich air-fuel mixture is introduced in a right direction. A rich air-fuel mixture diffusion part 657 is provided at an upper position of the first communication hole to diffuse the rich air-fuel mixture introduced upward from the first communication hole to both of right and left sides. Restriction parts 658 for flow rate stabilization are provided at lower side positions of the rich flame holes in the right side region, and a flow path expansion part 654 is provided in the longitudinal direction between the restriction parts and the rich flame holes to unify supply flow rate.

Description

  The present invention relates to a concentration burner having a concentration flame hole and a variation flame burner, and in particular, the variation flame holes are arranged on both sides in the short direction across the concentration flame hole extending in the longitudinal direction at the center position. Concentrated air-fuel mixture with a uniform flow rate and a stable flow rate over the entire length in the longitudinal direction of the thick flame burner with thick flame holes arranged on both outer sides in the short-side direction, with respect to the concentrated flame hole extending in the longitudinal direction at the center position It relates to technology that can be supplied.

Conventionally, a lean mixture having an air ratio larger than 1 is burned in the flare holes in order to reduce NOx, while a concentrated mixture having an air ratio smaller than 1 is used to stabilize the combustion flame. Various types of concentration combustion burners have been proposed in which the concentration flame hole for burning the gas is adjacent to the emission flame hole. And, as such a light and dark combustion burner, it is possible to form a light and dark combustion burner whose overall shape is flat by joining or welding together various forming members obtained by forming a thin plate material into a predetermined shape by press molding or the like. It has been proposed (see, for example, Patent Documents 1 to 3). In particular, in Patent Document 1,
When a plurality of strip-shaped rectifying plates are arranged in order with a predetermined gap between them, a plurality of slit-shaped flow passages each having a top flame opening as a light flame hole are formed, and lightly positioned below these. An inflow path for the air-fuel mixture is provided, and the width of the slit-shaped flow path directly above the inflow path is made narrower than the other slit-shaped flow paths, while the lower ends of the other two slit-shaped flow paths It has been proposed to provide a common space portion in each portion. Further, Patent Document 2 proposes that a rich mixture chamber, a light mixture chamber, and a means for mixing the two to communicate with each other to burn the mixture of three types of concentrations. . Furthermore, in Patent Document 3, as a flow path for supplying a rich mixture to two rows of concentrated flame holes extending in the longitudinal direction across the pale flame holes from both sides in the short direction, the longitudinal direction is located at the lower position of the concentrated flame holes. A tubular flow channel extending from one side to the other side and a vertical flow channel for supplying a rich air-fuel mixture to each concentrated flame hole from an intermediate position of the tubular flow channel are provided, and the vertical flow channel is formed wide in the longitudinal direction. In addition, it has been proposed to provide a plurality of inner protrusions so as to partially block the flow path.

JP 2010-261619 A JP 2003-329220 A JP 2011-191037 A

  By the way, it is not a concentration burning burner in which concentrated flame holes are arranged on both sides of a row of pale flame holes and the pale flame holes are simply sandwiched from both sides, but a row of dense flames is further extended on the center line of the pale flame holes. By adding flame holes, the development of a concentration burner with a configuration in which the flame holes and light flame holes are alternately arranged in the short-side direction (width direction), for example, in the arrangement of dark-light-dark-light-dense This is being done by the applicant. In this case, as a burner part for forming a concentrated flame hole at the center position, the two metal plate members are opposed to each other with a narrow slit-shaped space therebetween, and the periphery is partitioned. It is considered to form a flat shape by joining them together. Then, the rich air-fuel mixture is introduced into the slit-like space from the communication hole formed at the middle position in the longitudinal direction, which is the lower position of the pair in the slit-like space, and the introduced rich air-fuel mixture reaches the full length range in the longitudinal direction at the upper end. A configuration is considered in which the fuel is supplied to a long and narrow concentrated flame hole.

  However, with such a configuration, due to the narrow width of the slit-shaped space in the burner portion, the rich air-fuel mixture introduced from the intermediate position in the longitudinal direction of the lower position is spread throughout the longitudinal direction in the slit-shaped space. On the other hand, as a result of difficulty in diffusion, there is a possibility of inconvenience that the thick flame formed in the rich flame hole becomes non-uniform and unstable. For example, more rich air mixture flows to the portion near the rich gas mixture inlet or the rich flame hole in the flow direction of the thick flame hole introduced from the rich flame hole inlet, and the longitudinal direction There is a possibility that the supply flow rate of the rich air-fuel mixture will become uneven and the flow velocity may become unstable. As a result, it is considered that the concentrated flame is destabilized and becomes a cause of poor combustion.

  The present invention has been made in view of such circumstances, and the object of the present invention is to perform deep mixing from a communicating hole at a lower position and a middle position in the longitudinal direction with respect to the concentrated flame hole extending in the longitudinal direction. An object of the present invention is to provide a light and dark combustion burner that can equalize the supply flow rate of the rich air-fuel mixture supplied to the rich flame holes throughout the longitudinal direction when the gas is introduced. It is another object of the present invention to stabilize the flow rate of the rich air-fuel mixture supplied to the rich flame hole throughout the longitudinal direction in addition to uniformizing the supply flow rate.

  In order to achieve the above object, a central concentrated flame hole arranged to extend in the longitudinal direction at a central position, and two rows of pale flame holes arranged so as to sandwich the central concentrated flame hole from both sides in the short direction, And two rows of outer dense flame holes arranged so as to sandwich the pale flame holes on both sides from the outside, and the rich mixture introduced by the rich mixture introduction passage is supplied to the central rich flame hole. The following specific items are provided for the light and dark combustion burner configured as described above. That is, the central rich flame hole opened in the longitudinal direction at the upper end, and a flat space-like rich mixed gas supply passage for supplying the rich mixed gas to the central rich flame hole, a pair of plates And a communication hole is formed at the intermediate position in the longitudinal direction of the lower end portion of the forming member so as to open toward the inside of the rich gas mixture introduction passage. The rich mixture introduction passage and the rich mixture supply passage are communicated with each other through a hole. A rich mixture diffusing section for diffusing the rich mixture introduced into the rich mixture supply passage from the communication hole toward the both sides in the longitudinal direction is connected to the rich mixture supply passage in the forming member. It was decided to form at a position above the hole (claim 1).

  In the case of the present invention, the rich mixture flowing into the rich mixture supply passage from the communication hole flows upward and the collision or flow is suppressed in the rich mixture diffusion portion, so avoid the rich mixture diffusion portion. The current is divided and diffused on both sides of the one side in the longitudinal direction and the other side. Thereby, even if the communication hole is formed in the middle position in the longitudinal direction, the rich gas mixture that has flowed into the rich mixture supply passage from the communication hole, the concentrated flame hole formed over the entire length in the longitudinal direction, It is possible to supply in a state of being uniformly diffused without being biased toward the concentrated flame hole above the communication hole.

  As the central concentrated flame hole of the present invention, the upper end opening of the forming member is divided into a plurality of blocks with a closed portion formed by being closed at predetermined intervals in the longitudinal direction. Is formed at a position closer to one side in the longitudinal direction than the central concentrated flame hole belonging to the block existing in the region on the other side in the longitudinal direction from the dense mixture diffusion portion. In addition, it is possible to form a flow rate restricting portion in which the opposing surfaces of the forming member protrude inward in the short direction (Claim 2). By doing in this way, the communication hole is not formed at the longitudinal center position but at a position biased to one side in the longitudinal direction, and from the communication hole at a position biased to one side in the longitudinal direction with respect to the inside of the rich mixture supply passage. Even when a rich mixture is supplied, the internal pressure of the rich mixture diffused to the other side of the rich mixture supply passage by the rich mixture diffusing unit is increased by the flow rate restricting unit to supply the rich mixture A supply flow rate equivalent to the rich air-fuel mixture diffused to one side of the passage can be obtained. As a result, the supply flow rate of the rich mixture to the rich flame holes formed over the entire length in the longitudinal direction can be made uniform without affecting the bias of the formation positions of the communication holes.

  In addition, in this case, the flow rate stabilizing throttle portion is formed for all the blocks existing in the region on the other side in the longitudinal direction from the concentrated mixture diffusion portion except for the block located on the other end in the longitudinal direction. (Claim 3). By doing so, the rich mixture can be sufficiently supplied also to the rich flame holes belonging to the block which is located at the end in the longitudinal direction and is considered to be difficult to flow the rich mixture.

  Furthermore, the thick flame hole supply passage at the intermediate portion in the vertical direction sandwiched between the rich flame hole of each block and each of the flow rate restricting portions extends in the longitudinal direction with the opposing surfaces of the forming members being widened. A channel enlarged portion can be formed (claim 4). In this way, even if the gas flowed upward through the elongated vertical space between the flow rate restricting portions adjacent to each other in the longitudinal direction, the concentrated gas mixture that has been vigorously supplied is directly supplied to the concentrated flame hole as it is. In the previous stage of flowing into each concentrated flame hole, the concentrated air-fuel mixture is once flowed into the flow passage expanding portion, the flow rate of the concentrated air-fuel mixture is made uniform in the longitudinal direction, and the flow velocity is In addition, it is possible to supply each concentrated flame hole after stabilization in the longitudinal direction.

  As described above, according to the lean combustion burner of the present invention, the flow of the rich mixture flowing into the rich mixture supply passage from the communication hole and moving upward collides with or is suppressed by the rich mixture diffusing section. As a result, the flow of the rich air-fuel mixture can be diffused by being divided into both sides of the one side in the longitudinal direction and the other side. Thereby, even if the communication hole is formed in the middle position in the longitudinal direction, the rich gas mixture that has flowed into the rich mixture supply passage from the communication hole, the concentrated flame hole formed over the entire length in the longitudinal direction, It can be supplied in a state of being uniformly diffused without being biased toward the rich flame hole located above the communication hole.

  In particular, according to claim 2, the communication hole is formed not at the longitudinal center position but at a position biased to one side in the longitudinal direction, and the communication at a position biased to one side in the longitudinal direction with respect to the inside of the rich mixture supply passage. Even when a rich mixture is supplied from a hole, the internal pressure of the rich mixture diffused to the other side of the rich mixture supply passage by the rich mixture diffusing section is increased by the flow stabilization orifice, and the thick mixture is mixed. A supply flow rate equivalent to the rich air-fuel mixture diffused to one side of the air supply passage can be achieved. As a result, the supply flow rate of the rich mixture to the rich flame holes formed over the entire length in the longitudinal direction can be made uniform without affecting the bias of the formation positions of the communication holes.

  In addition, according to claim 3, as the flow rate stabilizing throttle portion, except for the block located at the other end in the longitudinal direction, all blocks existing in the region on the other side in the longitudinal direction from the concentrated mixture diffusion portion are targeted. By forming it, the rich mixture can be sufficiently supplied even to the rich flame holes belonging to the block which is located at the end in the longitudinal direction and is considered to be difficult to flow the rich mixture. become.

  Further, according to the fourth aspect, even if the gas flows upward through the elongated vertical space between the flow rate stabilizing throttle portions adjacent to each other in the longitudinal direction, the vigorous mixed gas directly flows into the rich flame hole as it is. In the previous stage of flowing into each concentrated flame hole, the concentrated mixture is once flowed into the flow passage expanding portion, the flow rate of the concentrated mixture is made uniform in the longitudinal direction, and The flow rate is stabilized in the longitudinal direction and can be supplied to each concentrated flame hole.

The example of the combustion apparatus incorporating the light and dark combustion burner of this invention is shown, FIG. 1 (a) is explanatory drawing shown in a perspective view state, FIG.1 (b) is explanatory drawing shown in a sectional view state. It is a perspective view of the light and dark combustion burner of the embodiment of the present invention. 3A is a plan view of the burner of FIG. 2, and FIG. 3B is an enlarged view of the FF portion of FIG. 3A. The first plate member constituting the light burner portion, the second plate member constituting the outer dark burner portion, the third plate member constituting the central dark burner portion, and the light disposed on both sides of the central dark burner portion It is a disassembled perspective view which shows the flame hole formation member which comprises a flame hole row | line | column in the state decomposed | disassembled. It is a decomposition | disassembly side view which shows the state which decomposed | disassembled of FIG. 4 in the state seen from the longitudinal direction one side. It is a perspective view shown in the state where the 3rd plate member of Drawing 4 or Drawing 5 was developed. It is a reference figure which shows the procedure which inserts a flame hole formation member in the state by which the 1st-3rd plate member was assembled | attached in an exploded state. It is a perspective view of the state cut | disconnected by the AA line of FIG. FIG. 9A is a front view showing a state cut along line AA in FIG. 2, and FIG. 9B is a partial view showing the central dark burner portion extracted from FIG. 9A. It is a fragmentary perspective view of the light and dark combustion burner when it cut | disconnects in the position corresponding to the BB line of Fig.9 (a). It is a fragmentary perspective view of the light and dark combustion burner when it cut | disconnects in the position corresponding to CC line of Fig.9 (a). It is a fragmentary perspective view of the light and dark combustion burner when it cut | disconnects in the position corresponding to the DD line of Fig.9 (a). FIG. 10 is a partially enlarged cross-sectional explanatory view in a state cut along the line EE in FIG. FIG. 10 is an enlarged cross-sectional explanatory view of the light and dark combustion burner when cut at a position corresponding to line BB in FIG. It is an expansion perspective view of the 3rd plate member which constitutes a central dark burner part. FIG. 10 is a partial perspective view of the central dark burner portion when cut at a position corresponding to the line GG in FIG. FIG. 10 is a partial perspective view of the central dark burner portion when cut at a position corresponding to the line HH in FIG. FIG. 10 is a partial perspective view of the central dark burner portion when cut at a position corresponding to line II in FIG. 9B. FIG. 19A is a partial perspective view of the central dark burner section when cut at a position corresponding to the line JJ of FIG. 9B, and FIG. 19B is a cross-sectional view of FIG. It is a fragmentary perspective view of a central dark burner part when it cut | disconnects in the position corresponding to a K line.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a combustion apparatus 2 to which a light and dark combustion burner according to an embodiment of the present invention is applied. This combustion apparatus 2 has a fixed burner set in a state where a predetermined number of light and dark combustion burners 3, 3,. The upper space of the can 21 is a combustion space 22, and combustion air from the blower fan 24 is supplied to the lower space 23, while a gas manifold 25 (see FIG. 1B) is provided on one side of each of the light and dark combustion burners 3. 2), and two gas nozzles 26, 27 protrude from the gas manifold 25 for each of the light and dark combustion burners 3. One (lower) gas nozzle 26 is directed toward the first supply port 31 of the concentration combustion burner 3, and the other (upper) gas nozzle 27 is injected toward the second supply port 32 of the concentration combustion burner 3. To get. Then, the air from the lower space 23 is pushed in from the surroundings of the gas nozzles 26 and 27 by the discharge pressure of the blower fan 24 so that both the fuel gas and the air can be supplied to the first and second supply ports 31 and 32. It has become. At this time, the first supply port 31 is set to have a considerably larger diameter than the second supply port 32, and more air is pushed in, while the second supply port 32 is set to a relatively small diameter, The amount of air to be pushed in is reduced. In this way, in addition to the fuel gas supplied from the first supply port 31, an amount of air having a predetermined air ratio larger than 1.0 times the amount of the fuel gas is supplied to the inside. On the other hand, in addition to the fuel gas similarly supplied from the second supply port 32, an amount of air having a predetermined air ratio smaller than 1.0 times the amount of the fuel gas is supplied to the inside. It has become. A large number of small holes are formed in the rectifying plate 28 (see FIG. 1B) arranged so as to partition the lower space 23 and the light and dark combustion burners 3, 3,... Secondary air is supplied between the light and dark combustion burners 3 and 3.

  As shown in FIG. 2, the light and dark combustion burner 3 is processed into a predetermined shape by pressing and bending using a metal plate material. That is, the concentration burner 3 includes a central concentration burner portion 3a composed of one row of rich flame hole rows 33, a light burner portion 3b composed of two rows of pale flame hole rows 34, 34, and two rows of rich flame hole rows. The outer thick burner portion 3c made of 35, 35 is formed in a flat shape as a whole, and these are three types of plate members 4, 4, 5, 5, 6 and a flame hole forming member 7. It is formed using. If the up-down direction in FIG. 3 is the longitudinal direction (front-rear direction) and the left-right direction in FIG. 3 is the short direction (width direction), the first supply port is located at the lower position on one side in the longitudinal direction (left side in FIG. 2). 31 is opened, a second supply port 32 having a smaller diameter than the first supply port 31 is opened at the upper position, and a plurality of flame hole arrays in which a combustion flame is formed on the upper end surface is formed in the longitudinal direction as shown in FIG. It is formed to extend. As the flame hole array, as shown in FIGS. 3A and 3B, a narrow flame hole array 33 having a narrow width extends in the longitudinal direction at the central position in the short direction, and this dense flame hole array 33 is formed. A relatively wide pale flame hole row 34 extends in the entire length in the longitudinal direction at each of both sides in the short direction, and a narrow deep flame hole row 35 is located at the outer side of the pale flame hole rows 34, 34 on both sides. It extends in the entire direction. Then, the light flame mixture supplied and mixed from the first supply port 31 (see FIG. 2) is guided to each of the pale flame holes 341 of the pale flame hole rows 34 and 34, and the pale flame is caused by each of the pale flames. A second supply port 32 (FIG. 2) is formed in each of the concentrated flame holes 331 of the concentrated flame hole array 33 at the center position and each of the concentrated flame hole arrays 351 of the two concentrated flame hole arrays 35, 35 at both outer positions. The rich mixture supplied and mixed from the reference is introduced, and a rich flame is formed by each of the rich mixtures.

  Such a light and dark combustion burner 3 can be formed as follows, for example. That is, as shown in FIG. 4 and FIG. 5, the three types of plate members 4, 4, 5, 5, 6 and the pair of flame hole forming portions 71, 71 are at least one (two in the illustrated example) bridge. The flame hole forming member 7 is integrally connected by the portions 72 and 72. The third plate member 6 (see FIG. 6) is arranged in a line-symmetric arrangement with a plate portion 65 on one side facing the metal plate material and a plate portion 65 on the other side across the folding line T. The plate material 6a is press-molded so as to be in a state of being formed, and after the molding, both the plate portions 65, 65 on both sides of the folding line T are inward (in the direction of the one-dot chain line arrow). The rear end edges 651 and 651 and the front end edges 652 and 652 are brought into close contact with each other. In the state after the bending, the bent portions along the fold line T are the lower end portions 60a and 60b (see also FIG. 4), and the plate portions 65 and 65 on both sides extending upward from the lower end portions 60a and 60b are predetermined. The gas mixture is opposed to each other at a narrow interval, and a supply passage for the rich mixture is formed between the opposed inner surfaces so as to communicate with the rich flame hole row 33 on the upper end surface. Further, along the fold line T, first communicating holes 61 are formed through the plate portions 65, 65 on both sides at the lower end portion 60a at the front end side position, and the unfolded plate material 6a (FIG. 6). In FIG. 4, a substantially diamond-shaped notch opening 601 is formed in advance at the rear position of the first communication holes 61, 61 with the folding line T interposed therebetween, and a notch recess 60c (see also FIG. 4) is formed in the bent state. It has come to be. In this way, the central dark burner portion 3a is formed by the third plate member 6. The pair of plate portions 65, 65 constitutes a pair of metal plate members, and the third plate member 6 constitutes a forming member composed of the pair of metal plate members. Each said 1st communicating hole 61 comprises the communicating hole of this invention.

  Then, by inserting the central dark burner portion 3a downward from the upper end opening between the pair of first plate members 4 and 4, the center between the pair of first plate members 4 and 4 facing each other in the short direction. The central dark burner portion 3a is disposed at the position (see FIG. 7), and the upper end openings of the first plate members 4 and 4 are divided into two by the central dark burner portion 3a. A flame hole forming member 7 is inserted into the upper end opening divided into two from above, and a pair of flame hole forming portions 71 and 71 constituting the flame hole forming member 7 are formed in the central dark burner portion 3a. The concentrated flame hole row 33 is assembled in a state of being surrounded from both sides in the short direction. At the time of this assembly, the bridging portions 72 and 72 of the flame hole forming member 7 are internally fitted in the concave fitting grooves 332 (see also FIG. 4) formed in the dense flame hole row 33 of the third plate member 6. . As a result, in the state where the positioning in the longitudinal direction and the positioning in the vertical direction are both performed, two rows of pale flame hole rows 34 and 34 (see also FIG. 3) are provided on the upper end surfaces of the pair of flame hole forming portions 71 and 71. ) Is formed, and the light burner portion 3b is formed. The second plate members 5 and 5 are placed on the outside of the first plate member 44 of the light burner portion 3b (see, for example, FIG. 5), and the outer dense flame hole rows 35 and 35 (see FIG. 3) are arranged on the upper end side. A supply passage is formed between the inner surface of each second plate member 5 and the outer surface of the first plate member 4 facing each other. Thus, the outer dark burner portion 3c (see FIGS. 2 and 3) is formed.

  The inner width between the inner surfaces 711 and 711 of the flame hole forming portions 71 and 71 (see FIG. 5) is the width dimension in the short direction of the central concentrated burner portion 3a formed by the third plate member 6 (specifically , And the outer width between the outer surfaces 710 and 710 on both sides of the pair of flame hole forming portions 71 and 71 is set to be the first plate. It is set so as to match the inner width of the members 4, 4 in the short direction (specifically, the inner surface spacing of bulging portions 44, 44 described later). Thus, if the pair of flame hole forming portions 71, 71 of the flame hole forming member 7 is inserted from above into the space between the third plate member 6 and the first plate members 4, 4 on both sides, The outer surface 710 of the flame hole forming portion 71 is in intimate contact with the inner surface of the first plate member 4 (specifically, the inner surface of the bulging portion 44), while the inner surface 711 of each flame hole forming portion 71 is the third plate member 6. The bulge portion 654 is in close contact with each other and is metal-sealed so that the air-fuel mixture does not pass between each other, and the pair of flame hole forming portions 71, 71 are securely in the short direction across the third plate member 6. Therefore, the third plate member 6 and the first plate members 4 and 4 can be reliably assembled at predetermined positions.

  As a supplementary explanation, the third plate member 6 has a rib-like bulging portion 654 that bulges outward in the lateral direction on the outer surface near the upper end of each plate portion 65 (see FIGS. 4 and 5). ) Extend in the entire length in the longitudinal direction, and the innermost surface 711 of each flame hole forming portion 71 is in close contact with the bulging portion 654. On the other hand, the first plate member 4 is also formed with a rib-like bulging portion 44 that bulges inward in the short-side direction so as to extend the entire length in the longitudinal direction. The outermost surface 710 of 71 will be in intimate contact. As a result, the metal seal is performed, and the deep flames formed in each of the thin flame hole rows 34 and the two rows of deep flames formed in the central rich flame hole row 33 and the outer rich flame holes 35 sandwiching this. A non-spouting zone 39, 40, 40, which is an air-fuel mixture non-spouting zone 39 extending in the entire length in the longitudinal direction in a band-like shape corresponding to a short lateral width corresponding to the bulging amount of the bulging portions 44, 654, 654, 44. 39 (see FIG. 14) can be formed.

  An appropriate number (two in the illustrated example) of protrusions 655 and 655 (see FIG. 4 and FIG. 5) projecting outward in the lateral direction are formed at positions near the upper ends of the plate portions 65 of the third plate member 6. Has been. Then, each flame hole forming portion 71 of the flame hole forming member 7 is inserted from above as described above, and the bridging portions 72 and 72 are fitted in the fitting grooves 332 and 332 and assembled. The projections 655 and 655 are fitted into the recesses formed on the inner surface 711 of each flame hole forming portion 71 so as to prevent the flame hole forming portions 71 from slipping upward. .

  Next, the supply structure portion of the light mixture and the rich mixture will be described with reference to FIGS. 8 and 9, the hatched portions are meshed surfaces that are brought into close contact with each other by intimate contact or pressure welding, and in addition, linear welding, spot welding, or the like is added, and the contact state is maintained. Maintained. As shown in FIG. 9A, in the light burner portion 3b, the fuel gas and air supplied from the first supply port 31 opened to one side are mixed in the cylindrical portion 36 to become a light mixture. The light mixture is sent to the other side through the cylindrical portion 36 (see the dotted line arrows in FIGS. 10 and 11) and turned from the other side to the upper side (see the dotted line arrows in FIG. 12). The space between the first plate members 4, 4 is supplied to each of the upper flame flame rows 34 through the two internal spaces 37, 37 partitioned (divided) by the lower end portion 60 b of the third plate member 6. It has become. The cylinder portion 36 and the internal spaces 37, 37 constitute a light mixture supply passage for supplying the light mixture to the two rows of the thin flame hole rows 34, 34, and the cylinder portion 36 has a first supply port 31. It also serves as a mixing chamber and an introduction passage (a light mixture introduction passage) for fuel gas and air supplied from the air. The third plate member 6 constitutes a forming member for partitioning and forming a first rich mixture supply passage, which will be described later, and the third plate member 6 bisects the downstream side of the light mixture introduction passage (2 The two fresh air-fuel mixture supply passages (internal spaces 37, 37) are partitioned.

  As for the rich air-fuel mixture, the fuel gas and air supplied to the second supply port 32 on the upstream end side are mixed in the cylinder portion 38 to become a rich air-fuel mixture. The mixture is further mixed while being led to the back (rear) closed end 381 side which is the downstream end side through (see also FIG. 13). The rich air-fuel mixture is supplied to each of the central dark burner portion 3a and the left and right outer dark burner portions 3c (see FIG. 10 or FIG. 11). That is, the lower end portion 60a on the front end side of the central dark burner portion 3a is inserted into the cylinder portion 38 from above and floats in a state of floating in the cylinder portion 38 (see also FIG. 10 or FIG. 14). The first communication holes 61, 61 are opened at positions above the mixing chamber (upper position), which is the internal space of the cylindrical portion 38, in the protruding portion (lower end portion 60 a). And the inner space 62 of the central dark burner portion 3a communicate with each other. As a result, the rich air-fuel mixture in the cylinder portion 38 is supplied to the rich flame hole row 33 through the first communication holes 61 and 61 and the internal space 62. In addition, the detailed supply until the rich air-fuel mixture introduced into the internal space 62 from the inside of the cylindrical portion 38 through the first communication holes 61 is supplied to the rich flame holes 331 constituting the central rich flame hole row 33. The structure portion will be described later.

  In addition, the second and third communication holes are formed in the pair of first plate members 44 constituting the cylindrical portion 38 at a position downstream of the opening positions of the first communication holes 61 and 61 (on the closed end 381 side). 41 and 41 (see also FIG. 11 or FIG. 13) are formed so as to penetrate, and the mixing chamber in the cylinder portion 38 is on one side by the second communication hole 41 on one side (the right side in FIG. 11 and the upper side in FIG. 13). The first plate member 4 communicates with the internal space 51 between the second plate member 5 on the same side as the first plate member 4, and the cylindrical portion 38 is formed by the third communication hole 41 on the other side (left side in FIG. 11, lower side in FIG. 13). The inner mixing chamber communicates with an internal space 52 between the first plate member 4 on the other side and the second plate member 5 on the same side. As a result, the rich air-fuel mixture in the cylinder portion 38 is supplied to the rich flame hole array 35 on one side through the second communication hole 41 and the internal space 51, while the rich air-fuel mixture in the cylinder portion 38 is similarly supplied to the other side. The concentrated flame hole array 35 on the other side is supplied through the third communication hole 41 and the internal space 52. In addition, the second communication hole 41 and the third communication hole 41 are set so as to open opposite to each other in the short direction at a position facing the notch recess 60c (see FIG. 9) of the third plate member 6. The pair of second and third communication holes 41 and 41 are configured to open to face each other through a space in the cylindrical portion 38 that does not block anything in the short direction (width direction) (see FIG. 11 or FIG. 13).

  In addition, the said cylinder part 38 comprises the mixing chamber for mixing the fuel gas and air which are supplied from the 2nd supply port 32, and the rich mixture introduction channel | path for introducing the mixed concentrated mixture On the other hand, the internal spaces 51, 52, 62 also serve to constitute a rich mixture supply passage for supplying the rich mixture to the corresponding rich flame hole rows 35, 33, 35. . That is, the internal space 51 that communicates with the second communication hole 41 constitutes the second rich mixture supply passage, and the internal space 52 that communicates with the third communication hole 41 constitutes the third rich mixture supply passage. An internal space 62 that communicates with the holes 61, 61 constitutes a first rich gas mixture supply passage that is partitioned into a flat space.

  Next, the supply structure portion of the rich air-fuel mixture in the central dark burner portion 3a will be described in detail. From the second supply port 32 that opens in the longitudinal direction one side (left side of the drawing) in the cylindrical portion 38 (see FIGS. 9A and 13), which is the rich mixture introduction passage, is directed to the other side (right side of the drawing). The rich air-fuel mixture that has flowed to the first communication holes 61 is introduced into the internal space 62 that is a rich air-fuel supply passage through the first communication holes 61, and finally the central rich flame hole array is passed through the internal space 62. 33 are supplied to the individual rich flame holes 331, and a rich flame is formed in each rich flame hole 331. As shown in FIGS. 9B and 15, the central deep flame hole row 33 is closed at the upper end opening between the plate portions 65, 65 by vertically closed portions 656, 656,... At predetermined intervals in the longitudinal direction. In addition, the inside of one block partitioned by the adjacent blocking portions 656, 656 is further divided into a plurality of (two in the illustrated example) small blocking portions, so that each block has, for example, three concentrated flame holes 331, 331, ... are formed in a compartment. On the other hand, a rich mixture diffusion portion 657, a predetermined number of flow stabilization orifices 658, 658,..., And a bulging portion 654 as a flow path expanding portion are formed in the internal space 62, The supply flow rate of the rich mixture to each of the rich flame holes 331 can be made uniform over the entire region in the longitudinal direction, and the flow rate of the rich mixture can be stabilized over the entire region in the longitudinal direction.

  That is, as shown in FIG. 16, the rich mixture diffusing portion 657 has a predetermined shape with each of the pair of plate portions 65, 65 partially protruding inward at a position above the first communication holes 61, 61. The range is formed by joining and closing each other. The shape is a triangular shape that is pointed downward, and is set to a shape that is diverted into a V shape as it goes upward from each first communication hole 61. Thus, when supplying the rich air-fuel mixture flowing from the first communication hole 61 at the intermediate position in the longitudinal direction to the rich flame holes 331, 331,... Formed over the entire length in the longitudinal direction, the first communication holes 61, 61 are provided. Thus, the rich mixture flowing into the internal space 62 can collide with the rich mixture diffusion portion 657 and can be divided and diffused to both sides of the one side in the longitudinal direction and the other side. In addition, the downward apex of the V-shape is positioned closer to the other side in the longitudinal direction (the right side in the drawing) than the position directly above each first communication hole 61. This is because even if the rich air-fuel mixture that has flowed through the cylindrical portion 38 (see FIG. 9A) to the other side in the longitudinal direction (the right side of the drawing) flows into the internal space 62 from the first communication holes 61, 61, This is due to the fact that it is considered to flow slightly diagonally upward to the right due to the influence of the flow direction in the cylindrical portion 38, not directly above the first communication hole 61 (see the broken arrow in FIG. 9B). ). That is, the main flow (center portion of the flow) of the rich mixture flowing in from the first communication hole 61 collides with the apex of the rich mixture diffusion portion 657, so that one side in the longitudinal direction and the other side Each of them can be diffused efficiently. In addition, the first communication holes 61, 61 are formed at positions closer to one side (left side) than the center position in the longitudinal direction (positions from 1/4 to 1/3 of the entire length in the longitudinal direction from the left end). Therefore, the other side portion in the longitudinal direction sandwiching the apex of the V-shape constituting the rich mixture diffusion portion 657 is longer than one side, and is formed with a gentle slope, thereby the rich mixture diffusion portion More concentrated air-fuel mixture than the one side (left side) is diffused with respect to the other side (right side) in the longitudinal direction than 657.

  In addition, each flow rate restricting portion 658 is closed at a predetermined position by a pair of plate portions 65 and 65 partially projecting inward in the same manner as described above and joining a predetermined shape range to each other. It is formed. The shape is a rectangle extending in the longitudinal direction by a predetermined range. Each flow stabilization throttle portion 658 is located below the rich flame holes 331, 331,... Belonging to a block in the range on the other side (right side) in the longitudinal direction from the formation position of the rich mixture diffusion portion 657, The bulging portion 654 is disposed at a position adjacent to the lower side. That is, as shown in FIGS. 17, 18 and 19A, each flow rate restricting portion 658 does not exist below the shielding portions 656 and 656 on both sides across one block, It arrange | positions so that it may exist in the downward position of the rich flame hole 331,331,331 between the adjacent shielding parts 656,656. As a result, the rich air-fuel mixture diffused to the other side in the longitudinal direction by the rich air-fuel mixture diffusing portion 657 flows upward vigorously through the elongated vertical space between the flow rate stabilizing throttle portions 658 and 658 adjacent in the longitudinal direction. Moreover, it is possible to prevent the rich air-fuel mixture that has flowed vigorously from being supplied directly to the rich flame hole 331 as it is. In addition, the flow rate of the rich mixture is made uniform in the longitudinal direction by once flowing the rich mixture into the flow passage expanding portion in the bulging portion 654 in the previous stage of flowing into each concentrated flame hole 331. In addition, the flow velocity can be stabilized in the longitudinal direction and then supplied to each concentrated flame hole 331. In addition, the rich air-fuel mixture whose flow velocity has been once reduced in the bulging portion 654, which is a flow passage expanding portion, is then placed in each concentrated flame hole 331 having the narrowest width compared to the internal space 62 and the flow passage expanding portion. Therefore, mixing is further promoted by the nozzle effect, and the rich air-fuel mixture in a state in which the mixing is promoted is ejected from the flame hole surface of each rich flame hole 331.

  However, the flow rate restricting portion 658 is not formed in the lower position of the rich flame holes 331 and 331 (see FIG. 19B) belonging to the block at the other end in the longitudinal direction (right end). Thereby, the rich mixture can be sufficiently supplied also to the rich flame holes 331 and 331 belonging to the block which is located at the end in the longitudinal direction and is considered to be difficult to flow the rich mixture.

  In the case of the above-described light and dark combustion burner 3, in addition to the characteristic effects described above, the following premise effects can be obtained. That is, since each of the two pale flame hole rows 34, 34 is sandwiched from both sides by the rich flame hole rows 35, 33 or the rich flame hole rows 33, 35, it is formed in both pale flame hole rows 34, 34. Each of the light flames can be surrounded by a thick flame from both sides. That is, the flame structure in the short direction can be arranged in the order of rich flame-light flame-rich flame-light flame-rich flame. As a result, even if the number of the light flame hole rows 34 is increased to increase the area of the light flame hole rows, the combustion of the combustion chamber 22 (see FIG. 1) is avoided while avoiding an increase in the flame length of the light flame. The chamber height can be kept low, while the combustion chamber height can be kept low, and the area (ratio) of the flare holes can be increased to further reduce NOx, and combustion can be further stabilized. Can be planned. In addition, compared with a case where one burner hole row is sandwiched between the dense flame hole rows from both sides to form one burner, the burner can be made more lightweight in terms of realizing the same pale flame hole area. become. Further, the rich air-fuel mixture introduced and mixed into the cylindrical portion 38 from one fuel gas and air supply port (second supply port 32) is communicated with the closed end side region of the cylindrical portion 38 and opened. Corresponding interior through the first communication holes 61, 61 of the central dark burner portion 3a, the second communication hole 41 of the outer dark burner portion 35 on one side, or the third communication hole 41 of the outer dark burner 35 on the other side. It is possible to divert (branch supply) the spaces 62, 51, 52. Thereby, even when three rich flame hole rows 35, 33, 35 are formed at the center and both outer sides, the rich mixture is smoothly and surely diverted with a simple structure so that each of the rich flame hole rows 35 is formed. , 33, 35. As described above, the central thick burner portion 3a is realized by a relatively thin thickness in the short direction, and is compact as a light and dark combustion burner that realizes an arrangement of rich flame-light flame-dark flame-light flame-rich flame. It can be realized with.

<Other embodiments>
A central deep flame hole row 33 composed of the central rich burner portion 3a and comprising a central rich flame hole 331, and a pair of pale flame hole rows 34 and 34 each comprising a pale flame hole 341 sandwiching this from both sides in the short direction; Further, in the case of the concentration burner provided with the outer dense flame hole row 35 composed of the outer dense flame holes 351 arranged so as to sandwich each pale flame hole row 34 from the outside, the pale burner portion shown in the above embodiment is used. The present invention can also be applied to a light and dark combustion burner adopting a configuration other than 3b and the outer dark burner portion 3c.

  In the above-described embodiment, the rich mixture diffusing portion 657 and the flow rate stabilizing throttle portion 658 are formed by partially protruding a pair of plate portions 65 and 65 toward the opposite surface side (inner side) and joining each other. However, the present invention is not limited to this, and it is possible to form a dense mixture diffusion part and a flow rate restricting part by making each part projecting and non-joining and partially narrowing. Also good. In short, it is only necessary to be able to diffuse or substantially block by suppressing the flow of the rich air-fuel mixture.

6 Third plate member (forming member)
33 Centered deep flame hole (central rich flame hole)
34 Pale flame hole train (Pale flame hole)
35 Outer deep flame hole train (outer rich flame hole)
38 cylinder part (rich mixture introduction passage)
60a Lower end (lower end of the forming member)
61 1st communication hole (communication hole)
62 Internal space (rich mixture supply passage)
65 Plate part (plate-like member)
331 Condensed flame hole 654 bulging part (flow path expanding part)
656 Shielding part 657 Rich mixture diffusion part 658 Restriction part for flow rate stabilization

Claims (4)

A central deep flame hole arranged to extend in the longitudinal direction at the central position, two rows of fine flame holes arranged so as to sandwich the central rich flame hole from both sides in the short direction, and the pale flame holes on both sides Further, there are two rows of outer rich flame holes arranged so as to be sandwiched from the outside, and the concentration is configured so that the rich mixture introduced by the rich mixture introduction passage is supplied to the central rich flame hole A combustion burner,
The central concentrated flame hole opened in a state of extending in the longitudinal direction at the upper end, and a flat space-like concentrated mixture supply passage for supplying the concentrated mixed gas to the central concentrated flame hole are a pair of plate-like members. A communicating hole is formed at the middle position in the longitudinal direction of the lower end portion of the forming member so as to open toward the inside of the concentrated air-fuel mixture introducing passage, and through the communicating hole. The rich mixture introduction passage and the rich mixture supply passage communicate with each other;
The rich mixture supply passage in the forming member has a rich mixture diffusion portion for diffusing the rich mixture introduced from the communication hole into the rich mixture supply passage toward both longitudinal sides. A light and dark combustion burner characterized by being formed at an upper position. The light and dark combustion burner according to claim 1,
The central concentrated flame hole is divided into a plurality of blocks across a closed portion in which the upper end opening of the forming member is closed at predetermined intervals in the longitudinal direction,
While the communication hole is formed at a position closer to one side in the longitudinal direction than the central position in the longitudinal direction, the concentrated mixture supply passage is formed in a block existing in a region on the other side in the longitudinal direction from the concentrated mixture diffusion portion. A concentration combustion burner, in which a flow rate restricting portion is formed at a position below the central concentrated flame hole to which the opposing surface of the forming member protrudes inward in the short direction. The light and dark combustion burner according to claim 2,
The flow rate stabilizing throttle part is formed for all the blocks existing in the region on the other side in the longitudinal direction than the dense mixture diffusion part except for the block located on the other side end in the longitudinal direction. Burner. The light and dark combustion burner according to claim 2 or 3,
A thick flame hole supply passage at an intermediate portion in the vertical direction sandwiched between the thick flame holes of each block and the respective flow rate stabilizing throttle portions extends in the longitudinal direction with the opposing surfaces of the forming members widened. A light and dark combustion burner in which a channel expansion part is formed.

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