Patent Publication Number: US-10309645-B2

Title: Gas supply manifold and gas combustion device provided with the same

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a gas supply manifold for use in a constitutional element of a gas powered water heating apparatus and a gas combustion device provided with the gas supply manifold. 
     Description of the Related Art 
     Generally, a gas combustion device provided for a gas powered water heating apparatus has a plurality of burner heads (combustion pipes) for burning fuel gas arranged in a burner case and fuel gas is supplied from a gas supply manifold into the burner heads. 
     The gas supply manifold is disclosed in, for example, Patent Literatures 1 and 2. The gas supply manifold disclosed in these Patent Literatures has a main body provided with a plurality of gas injection nozzles and has a cover member overlapped on the main body via a sealing packing. The cover member constitutes a gas supply flow path between the cover member and the main body and is fastened to the main body with a screw. The cover member and the main body are manufactured by pressing a metal plate. 
     In such a configuration, the number of members and the production cost of the gas supply manifold are reduced. In addition, the gas supply manifold is made thin and the weight is reduced. 
     However, there is still room for improvement in the related art as mentioned below. 
     It is desired that the production cost of the gas supply manifold be further reduced and the weight reduction be further promoted comparing with the related art. For this purpose, the thickness (sheet thickness) of the cover member can be reduced. However, when the thickness is merely reduced, the cover member easily twists and causes deformation such as warp. Such deformation causes leakage of fuel gas out of the gas supply flow path formed between the cover member and the main body. Therefore, there is need for appropriately preventing such problems. 
     The number of screwed portions of the cover member to the main body can be increased for suppressing warp and deformation of the cover member. In such a case, the screwing procedure becomes complicated and the production cost increases. Further, even when the number of the screwed portions is increased, it is difficult to adequately suppress warp and deformation of the cover member. 
     CITATION LIST 
     
         
         Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2004-197971 
         Patent Literature 2: Japanese Unexamined Patent Application Publication No. 2003-065507 
       
    
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a gas supply manifold capable of solving or suppressing the above-mentioned disadvantages and to provide a gas combustion device provided with the gas supply manifold. 
     In order to solve the above-mentioned problems, the present invention proposes the following technical means. 
     A gas supply manifold in one aspect of the present invention includes a main body having a plurality of gas injection nozzles, a cover member overlapped on one side of the main body and coupled with the main body, a gas supply flow path formed between the cover member and the main body and communicating with the plurality of gas injection nozzles, and a bent rising wall portion formed by bending a part of the cover member so as to rise opposite to the main body, the bent rising wall portion being in a form of a loop surrounding an entire circumference of the gas supply flow path and an area around the gas supply flow path when viewed in an overlapping direction of the cover member and the main body. 
     Preferably, the bent rising wall portion is formed so as to entirely overlap the main body when viewed in the overlapping direction. 
     Preferably, the main body has a plurality of openings for inflow of gas apart from the plurality of gas injection nozzles, and the cover member has a plurality of bulging portions and a non-bulging portion at an area surrounded with the bent rising wall portion, the bulging portions extending toward the plurality of gas injection nozzles from the plurality of openings when viewed in the overlapping direction and bulging in a direction apart from the main body, the non-bulging portion with a flat front face being positioned around the plurality of bulging portions. In addition, each of the bulging portions includes a space constituting the gas supply flow path connecting each of the openings and each of the gas injection nozzles when the cover member is overlapped on the main body in such a manner that the non-bulging portion faces and contacts the one side of the main body. 
     Preferably, the cover member is manufactured by pressing a metal plate. 
     Preferably, the main body and the cover member are fastened by a plurality of screwing members. 
     Preferably, the gas supply manifold further includes a sealing packing interposed between the cover member and the main body, and a convex positioning portion provided for the cover member to be inserted into a hole provided for the sealing packing. The main body has a concave portion that is not penetrated and is dent in a projecting direction of the convex positioning portion through which a tip end of the convex positioning portion goes. 
     Preferably, the cover member further has a flange portion that is connected with a tip end of the bent rising wall portion and that is bent, the flange portion protruding out of the main body when viewed in the overlapping direction, and the flange portion is used as an attachment portion when the gas supply manifold is attached to an objective attachment member. 
     Preferably, the gas supply manifold further includes a bent piece integrally connected with the flange portion so as to be bent from an outer peripheral edge of the flange portion. 
     A gas combustion device in the second aspect of the present invention includes the gas supply manifold of the first aspect of the present invention. 
     A gas combustion device in the third aspect of the present invention includes a burner case housing a plurality of burner heads, a gas supply manifold facing and contacting an outer face of the burner case, and supplying fuel gas to the plurality of burner heads, and a loop-like sealing packing interposed between the gas supply manifold and the outer face of the burner case. The gas supply manifold proposed in the first aspect of the present invention is used for the gas supply manifold, the flange portion protrudes from an upper part of the main body and from right and left ends of the main body, and a part of the loop-like sealing packing is under the plurality of gas injection nozzles on a front face of the main body and extends in a width direction, and the other of the loop-like sealing packing is on a front face of the flange portion. 
     The other characteristics and advantages of the present invention are apparent from the following explanation of the preferred embodiments referring to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a front view of one embodiment of a gas supply manifold of the present invention, and 
         FIG. 1B  is the back view. 
         FIG. 2A  is a sectional view of the embodiment taken along the line IIa to IIa in  FIG. 1A ,  FIG. 2B  is a sectional view taken along the line IIb to IIb in  FIG. 1B , and  FIG. 2C  is a sectional view taken along the line IIc to IIc in  FIG. 1A . 
         FIG. 3  is an essential sectional view of the embodiment taken along the line III to III in  FIG. 1B . 
         FIG. 4  is an exploded front view of the gas supply manifold shown in  FIG. 1A  and  FIG. 1B . 
         FIG. 5A  is a perspective back view of the cover member of the gas supply manifold shown in  FIG. 1A  and  FIG. 1B ,  FIG. 5B  is a sectional view taken along the line Vb to Vb in  FIG. 5A , and  FIG. 5C  is a sectional view taken along the line Vc to Vc in  FIG. 5A . 
         FIG. 6  is an essential sectional view of one embodiment in which the gas supply manifold shown in  FIG. 1A  and  FIG. 1B  is incorporated into a burner case. 
         FIG. 7  is a front view of an example when a loop-like sealing packing used in the structure shown in  FIG. 6  is attached. 
         FIG. 8  is a sectional view of a comparison example relative to the embodiment shown in  FIG. 1A . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Preferred embodiments of the present invention are explained below with reference to the accompanying drawings. 
     An arrow Fr in some drawings indicates the forward direction in the following explanation. 
     A gas supply manifold A shown in  FIG. 1A  to  FIG. 2C  supplies fuel gas to a plurality of burner heads (combustion pipes)  91  housed in a burner case  90  of a gas combustion device B as shown in  FIG. 6 . Specific structure of the gas combustion device B is explained later. 
     In  FIG. 1A  to  FIG. 2C , the gas supply manifold A has a main body  2 , a cover member  1  overlapped on a rear face of the main body  2 , and a sealing packing  3  interposed between the main body  2  and the cover member  1 . The main body  2  and the cover member  1  are manufactured by pressing metal plates. 
     The main body  2  is a nozzle plate, and a plurality of gas injection nozzles  25  projecting in a forward direction of the main body  2  are provided at the upper area of the main body  2 . A plurality of gas supply flow paths  29  communicating with the gas injection nozzles  25  are provided between the main body  2  and the cover member  1 . Fuel gas is flown into the gas supply flow paths  29  from a plurality of openings  26  provided at the lower area of the main body  2 . A plurality of bulging portions  18  are provided so as to form the gas supply flow paths  29 , the bulging portions  18  bulging in a direction apart from the main body  2  and being in the form of a stripe when viewed from the back. The bulging portions  18  extend toward the gas injection nozzles  25  from the openings  26 , and the inside of each bulging portion  18  constitutes the gas supply flow path  29 . 
     The cover member  1  has a bent rising wall portion  11  ( 11   a ,  11   b ), a flange portion  12 , and a pair of convex portions  13  for positioning the sealing packing  3 , the convex portions  13  provided on the right and the left, further referring to  FIG. 5A  to  FIG. 5C . 
     The bent rising wall portion  11  is formed by bending a part of the cover member  1  around the area where the plurality of gas supply flow paths  29  are formed so as to rise toward the back face of the cover member  1  and is in the form of a loop surrounding the entire circumference of the gas supply flow paths  29  and the area around the gas supply flow paths  29  when viewed in the front-rear direction of the cover member  1 . The expression “when viewed in the front-rear direction” is one example of “when viewed in the overlapping direction” of the cover member and the main body in the description of the present invention. Specifically, the bent rising wall portion  11  is in the form of a loop similar to the outline of the main body  2  when viewed in the front-rear direction. 
     The bent rising wall portion  11  is sectioned into an upper bent rising wall portion  11   a  ( 11 ) and a lower bent rising wall portion  11   b  ( 11 ). The upper bent rising wall portion  11   a  is close to the upper part of the cover member  1 , and a tip end of the upper bent rising wall portion  11   a  is connected to the flange portion  12 . The lower bent rising wall portion  11   b  is integrally connected with the upper bent rising wall portion  11   a  and is close to the lower part of the cover member  1 . In this embodiment, as shown in  FIG. 2B , the rising height Ha of the upper bent rising wall portion  11   a  is larger than the rising height Hb of the lower bent rising wall portion  11   b . However, the present invention is not limited to such an embodiment, and the height Ha can be equal to the height Hb or the height Ha cannot be equal to the height Hb. 
     The entire loop-like bent rising wall portion  11  approximately overlaps with the main body  2  when viewed in the front-rear direction of the gas supply manifold A. The almost all of the area of the cover member  1  surrounded with the bent uprising wall  11  constitutes an overlapping area  10  overlapped with the main body  2 . The overlapping area  10  of the cover member  1  is fastened to the main body  2  by means of a plurality of screws  50  (screwing members). In the area around the plurality of the bulging portions  18  (the area other than the bulging portions  18 ), a front face of the overlapping area  10  facing the main body  2  basically constitutes a flat non-bulging portion  18   a.  The screws  50  are fastened in such a manner that the non-bulging portion  18   a  faces and contacts the back face of the main member  2  through the sealing packing  3 . 
     A pair of convex positioning portions  13  are provided at right and left ends of the overlapping area  10  of the cover member  1  or are provided around the right and left ends. The convex positioning portions  13  are formed by making a hole  13   a  on the cover member  1  and by rising the area around the hole  13   a , namely a rising process, and projects forward from the cover member  1 . For assembling the gas supply manifold A, for example, the packing  3  is mounted on a front face of the cover member  1 , then the main body  2  is mounted the packing  3 , and all of them are fastened, as shown in  FIG. 4 . The convex positioning portions  13  are inserted into holes  30  provided at the right and left ends of the packing  3  or around the right and left ends when the packing  3  is mounted on the front face of the cover member  1 . 
     Concave portions  22  dented in a forward direction of the main body  2  are formed on the back face of the main body  2  corresponding to the convex positioning portions  13 . As shown in  FIG. 3 , a tip end of the convex positioning portion  13  goes through the concave portion  22 . The concave portion  22  is formed by making a step, namely a step press working, on the main body  2  and is not penetrated. 
     The flange portion  12  is connected to the tip end of the bent rising wall portion  11  and is bent in a direction intersecting with the bent rising wall portion  11 . The flange portion  12  has an upper portion  12   a  protruding from the upper part of the main body  2  and has right-left ends  12   b  protruding from the right and left ends of the main body  2 . The flange portion  12  has a plurality of holes  14  for screwing and the gas supply manifold A is attached to an objective attachment portion using the flange portion  12 . A bent piece  15  for reinforcing the flange portion  12  is further provided for an outer peripheral edge of the flange portion  12 . The outer peripheral edge of the flange portion  12  has an area  16  without having the bent piece  15 , and the area  16  works as a portion supporting the cover member  1  when the cover member  1  is manufactured by “a progressive press working”. 
     The gas supply manifold A is used for a constitutional component of the gas combustion device B shown in  FIG. 6 , for example. 
     The basic structure of the gas combustion device B is similar to the gas combustion device disclosed in Patent Literature 1 and has the plurality of burner heads  91  arranged in a direction intersecting with the sheet of the figure, the burner case  90  having an upper opening and housing the burner heads  91 , a fan  93  for supplying combustion air into the burner case  90  from the lower part of the burner case  90 , and an ignition plug  94 . When fuel gas and combustion air are mixed and flow in the burner head  91  from gas supply ports  92   a ,  92   b , the fuel gas burns on a flame bore face  92   c  formed on an upper face of the burner heads  91 . When a heat exchanger, not shown, capable of communicating heated water is provided on the burner case  90 , water is heated by the gas combustion device B, thereby constituting a gas powered water heating apparatus. 
     In the gas combustion device B, the gas supply manifold A is set as below. An auxiliary member  8  having a plurality of on-off valves V for supplying fuel gas is provided at a lower part of a front face of the main body  2 . Fuel gas supplied from a gas pipe, not shown, flows into the gas supply flow paths  29  through a gas supply flow path  81  in the auxiliary member  8  and through the openings  26  of the main body  2 . The on-off valves V are capable of opening or closing the openings  26 . The auxiliary member  8  is appropriately provided with a flow control valve and so on, not shown. 
     The flange portion  12  is screwed to the burner case  90 , thereby attaching the gas supply manifold A to an outer face of the burner case  90 . In such a case, the plurality of gas injection nozzles  25  face and contact the gas supply ports  92   a ,  92   b  of the burner heads  91  and fuel gas is supplied to the gas supply ports  92   a ,  92   b.    
     For attaching the gas supply manifold A, a loop-like sealing packing  4  made of an elastic material is used. The loop-like packing  4  is, for example, in the form of a loop that is substantially rectangular when viewed from the front as shown in  FIG. 7 . A part of the loop-like packing  4  is provided under the plurality of gas injection nozzles  25  on the front face of the main body  2  and extends in the width direction from side to side. The other part of the loop-like packing  4  is positioned on a front face of the flange portion  12  of the cover member  1 . A step-like difference is generated between the front face of the flange portion  12  and the front face of the main body  2  in the back-and-forth direction of the gas supply manifold A. The loop-like packing  4  is made of a flexible material and is prepared so as not to produce a gap at the difference. 
     In the embodiment of  FIG. 6  in which the gas supply manifold A is attached, the loop-like packing  4  is positioned so as to surround the entire circumference of the area where the plurality of gas injection nozzles  25  are provided when viewed from the front of the burner case  90  and is compressed between the gas supply manifold A and the burner case  90 . Therefore, fuel gas injected from the gas injection nozzles  25  is appropriately prevented from leaking out of the loop-like packing  4 . 
     Next, the functions of the gas supply manifold A and the gas combustion device B provided with the same are explained. 
     The loop-like bent rising wall portion  11  of the cover member  1  is provided so as to surround the entire circumference of the plurality of the gas supply flow paths  29  and the area around the gas supply flow paths  29 , thereby increasing the strength of such an area. Different from the embodiment of the present invention, if the cover member  1  is partially provided with a non-loop bent rising wall portion, it is difficult to efficiently reinforce the wide area including and around the gas supply flow paths  29  and the cover member  1  may be warped and deformed. On the other hand, in the present invention, there is such an advantage that the loop-like bent rising wall portion  11  eliminates warping and deformation of the cover member  1 , and eliminates distortion of the gas supply flow paths  29  and the area around the gas supply flow paths  29 . 
     The entire loop-like bent rising wall portion  11  approximately overlaps with the main body  2  when viewed in the front-rear direction, thereby efficiently reinforcing the gas supply flow paths  29  and the area around the gas supply flow paths  29 .  FIG. 8  illustrates a comparison example with the embodiment of the present invention, and the upper and lower bent rising wall portions  11   a ,  11   b  ( 11 ) protrude from the main body  2  in appropriate widths La, Lb. This comparison example is included in the technical field of the present invention. However, in the comparison, the bent rising wall portion  11  with high rigidity does not strongly contact the main body  2  under pressure. On the other hand, in the embodiment of the present invention, the bent rising wall portion  11  with high rigidity is able to strongly contact the main body  2  under pressure. In addition, the dimension of the area surrounded with the loop-like bent rising wall portion  11  is smaller than that of the comparison. Therefore, in the embodiment of the present invention, the gas supply flow paths  29  and the area around the gas supply flow paths  29  are further effectively reinforced. 
     As mentioned above, even when the thickness of the cover member  1  is comparatively reduced, large distortion is not caused around the gas supply flow paths  29  of the cover member  1  and the area around the gas supply flow paths  29 , and the main body  2  and the cover member  1  do not generate the gap causing gas leakage from the gas supply flow paths  29 . In addition, there is no need for increasing the number of the screwing portions for fastening the cover member  1  and the main body  2  in order to prevent gas leakage. Therefore, the weight and production cost of the gas supply manifold A are reduced, and further the weight and production cost of the gas combustion device B are appropriately reduced. 
     As shown in  FIG. 3 , the projecting dimension of the convex positioning portion  13  is made larger than the thickness of the packing  3  since the convex positioning portion  13  goes through the concave portion  22  of the main body  2 . That fact is preferable to prevent the positioning convex portion  13  from coming off the holes  30  of the packing  3  and to improve assembly performance of the packing  3  when the packing  3  is assembled to the cover member  1 . On the other hand, the concave portion  22  of the main body  2  is a non-penetrating hole and gas does not leak out through the concave portion  22 . 
     In this embodiment, as explained referring to  FIG. 6  and  FIG. 7 , the flange portion  12  of the cover member  1  is used for attaching to the burner case  90 , so that there is no disadvantage such that the attachment performance of the gas supply manifold A is deteriorated due to the fact that the cover member  1  is provided with the loop-like bent rising wall portion  11 . The loop-like packing  4  appropriately prevents leakage of fuel gas injected from the plurality of the gas injection nozzles  25 . The loop-like packing  4  is preferably positioned on the front face side of the flange portion  12  and the main body  2 . 
     The present invention is not limited to the above-mentioned preferred embodiments. The concrete configuration of the members of the gas supply manifold and the gas combustion device in the present invention is freely designed within the intended scope of the present invention. 
     The specific configuration (loop-like shape) and specific rising dimension of the bent rising wall portion in the present invention are not limited. 
     It is not limited that the cover member and the main body are fastened by a screw. They can be fastened by means of a screwing member other than a screw. In place of or in addition to the screwing member, a caulking means can be used. 
     The gas combustion device of the present invention is not limited to a gas powered water heating apparatus and can be used for heating or incinerating. The specific usage is not limited.