Combustion device

Abstract

A combustion device is provided with a combustion chamber (2) and a gas supply chamber (3) on the lower side of the combustion chamber in a combustion housing (1). Air supplied from a fan to the gas supply chamber is supplied as primary air to each burner (5) in the combustion chamber, and as secondary air to the combustion chamber via distribution holes formed in a partition plate (4) on the upper surface of the gas supply chamber. An air flow inlet for the air from the fan to flow into the gas supply chamber is formed in at least one of the rear wall surface and the lateral side wall surface of the gas supply chamber. A baffle plate (35) is provided in the gas supply chamber opposite the air flow inlet and causes a portion of the air flowing in from the air flow inlet to rebound toward the air flow inlet. In addition, a shelter portion (36) is provided that extends from the upper edge of at least a portion of the air flow inlet toward the inside of the gas supply chamber. The air is thus easily supplied to the distribution holes formed in the portion of the partition plate closer to the air flow inlet.

Description

TECHNICAL FIELD

[0001] The present application relates to a combustion device provided with a combustion housing in which a combustion chamber in which a plurality of burners are housed side by side in the lateral direction, and a gas supply chamber separated from the combustion chamber by a partition plate and positioned on the lower side of the combustion chamber are provided, the front surface of the gas supply chamber is blocked by a gas manifold for supplying fuel gas to the plurality of burners, air supplied from a fan to the gas supply chamber is supplied to each burner as primary air from the front of the gas supply chamber, and is supplied to the combustion chamber as secondary air through a plurality of distribution holes formed in the partition plate. BACKGROUND

[0002] In the past, in such a combustion device, generally, an air flow inlet through which air from the fan flows into the gas supply chamber is provided in the bottom surface of the gas supply chamber, but a combustion device in which an air flow inlet is provided in at least one of the rear wall surface and the lateral side wall surface of the gas supply chamber is also known (for example, refer to Patent Literature 1).

[0003] Here, according to the latter of the above-described conventional examples, the fan can be disposed at a position that is at or higher than the level of the gas supply chamber outside the combustion housing. Thus, if compared with the former of the above-described conventional examples in which the fan needs to be disposed at a position further downward than the combustion housing, it has the advantage that the height dimension of the entire combustion device including the fan can be shortened.

[0004] However, according to the latter of the above-described conventional examples, since the air flows into the gas supply chamber almost without having an upward directional component, the air is difficult to flow into the distribution holes formed in the portion of the partition plate close to the air flow inlet. Therefore, the portion of the combustion chamber close to the wall surface in which the air flow inlet is provided is likely to have a situation in which the secondary air is insufficient and combustion is poor.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Laid-Open No. 2014-59114 SUMMARY

[0008] The present application, in view of the above-described problems, aims to provide a combustion device in which an air flow inlet is provided in at least one of the rear wall surface and the lateral side wall surface of the gas supply chamber, and air easily flows into the distribution holes formed in the portion of the partition plate close to the air flow inlet.

[0009] To solve the aforementioned problems, the combustion device of the present invention includes a combustion housing, within which are disposed a combustion chamber that houses multiple burners side by side in a transverse direction, and an air supply chamber separated from the combustion chamber by a partition plate and located below the combustion chamber. The front surface of the air supply chamber is blocked by a gas manifold for supplying fuel gas to the multiple burners. Air supplied from a fan to the air supply chamber is supplied to each burner as primary combustion air from the front of the air supply chamber, and is supplied to the combustion chamber as secondary combustion air via multiple distribution holes formed in the partition plate. An air inlet for allowing air from the fan to flow into the air supply chamber is provided on at least one of the rear wall surface and the side wall surface on the transverse side of the air supply chamber. The invention is characterized in that an impact plate (impact plate) is provided in the air supply chamber opposite to the air inlet and for causing a portion of the air flowing in from the air inlet to bounce back toward the air inlet side.

[0010] According to the present invention, since a portion of the air flowing in from the air inlet bounces off the impeller plate and rebounds towards the air inlet side, the air can easily flow into the distribution holes formed in the portion of the partition plate closer to the air inlet. Therefore, it is possible to suppress the insufficient secondary air in the portion of the combustion chamber closer to the wall where the air inlet is located.

[0011] Furthermore, in this invention, it is preferable that the upper edge of the impact plate is located at a height above the center of the air inlet in the vertical direction. This allows air flowing in from the air inlet to be effectively bounced back towards the air inlet side.

[0012] Furthermore, in this invention, when the air inlet is located on one of the rear wall surface or the side wall surface on the lateral side of the air supply chamber, it is preferable that the thrust plate is inclined such that, when viewed from above, it approaches the wall surface of the air supply chamber where the air inlet is located from the center of the long side towards each end of the long side. Accordingly, air will easily flow from each end of the thrust plate along the wall portion of the air supply chamber adjacent to the end of the air inlet. Consequently, air will also easily flow into the distribution holes formed in the partition plate portion closer to this wall portion, thereby making the distribution of secondary air in the combustion chamber more uniform.

[0013] Furthermore, when the air inlet is located on both the rear wall and the side wall on the lateral side of the air supply chamber, and air from the fan flows into the air supply chamber from the air inlet with a forward component that is inclined towards the other lateral side, it is difficult for air to flow into the vicinity of the portion of the side wall on the lateral side of the air supply chamber adjacent to the front end of the air inlet. Therefore, in this case, it is preferable that the upright plate has: a first plate portion opposite to the portion of the air inlet located on the rear wall of the air supply chamber; and a second plate portion opposite to the portion of the air inlet located on the side wall on the lateral side of the air supply chamber, which, when viewed from above, is forward-leaning and inclined towards the lateral side. Accordingly, air can easily flow in from the front end of the second plate portion along the portion of the side wall on the lateral side of the air supply chamber adjacent to the front end of the air inlet, thereby eliminating the aforementioned undesirable situation.

[0014] Furthermore, when the fan is positioned higher than the air supply chamber on the outside of the combustion chamber, and air is supplied to the air inlet via a channel located below the fan, the air will bounce upwards on the lower surface of the channel near the air inlet. Sometimes, this air will collide with the air bouncing off the baffle plate below the baffle plate near the air inlet, thus creating a vortex. Moreover, once a vortex is generated, it will obstruct the airflow into the distribution holes formed in the baffle plate near the air inlet.

[0015] Therefore, when the fan is positioned higher than the air supply chamber on the outside of the combustion chamber, and air is supplied to the air inlet via a channel located below the fan, it is preferable to provide a protective portion extending from at least a portion of the upper edge of the air inlet toward the inside of the air supply chamber. Accordingly, air rebounding upwards from the lower surface portion of the channel near the air inlet will encounter the protective portion instead of colliding with air rebounded by the baffle plate and directed toward the protective portion. As a result, vortices generated below the portion of the baffle plate closer to the air inlet can be suppressed, allowing air to flow well into the distribution holes formed in the portion of the baffle plate closer to the air inlet.

[0016] Furthermore, when the air inlet is located on both the rear wall and the side wall of the air supply chamber, air from the fan flows into the air supply chamber with a forward-leaning component and a lateral component tilted towards the other side. If the fan is positioned higher than the air supply chamber outside the combustion chamber, and air is supplied to the air inlet via a channel located below the fan, the upward rebound of air at the lower surface of the channel in the portion of the air inlet located on the rear wall of the air supply chamber, near the other side, becomes significant. Therefore, in this case, it is sufficient to provide a protective portion extending inwards from at least the upper edge of the portion of the air inlet located on the rear wall of the air supply chamber, near the other side.

[0017] Furthermore, the length of the protective section extending inward toward the air supply chamber is preferably set such that at least the distribution hole closest to the upper edge of the air inlet where the protective section is located overlaps with the protective section when viewed from below. This reliably prevents the formation of vortices below the distribution hole closest to the upper edge of the air inlet, thus avoiding obstruction of airflow into that distribution hole. Attached Figure Description

[0018] Figure 1 This is a perspective view showing the combustion device of the first embodiment of the present invention viewed from a slightly forward and upward angle.

[0019] Figure 2 This is a perspective view showing the combustion device of the first embodiment of the present invention viewed from a slightly rearward and upward angle.

[0020] Figure 3 This is a top view showing the combustion device according to the first embodiment of the present invention.

[0021] Figure 4 It means along Figure 3 A sectional side view obtained by cutting along line IV-IV.

[0022] Figure 5 It means along Figure 4 The sectional top view obtained by cutting along line V-V.

[0023] Figure 6 It means along Figure 4 The front view obtained by cutting along line VI-VI.

[0024] Figure 7 This refers to the second embodiment of the present invention. Figure 5 The corresponding sectional bottom view.

[0025] Explanation of reference numerals in the attached figures

[0026] 1…combustion shell; 2…combustion chamber; 3…air supply chamber; 31…front part of air supply chamber; 32…rear wall of air supply chamber; 33…side wall of the transverse side of air supply chamber; 34…air inlet; 35…pump plate; 351…first plate part; 352…second plate part; 36…protection part; 4…partition plate; 41…distribution plate; 5…burner; 6…fan; 7…gas manifold; 8…channel. Detailed Implementation

[0027] Below, refer to Figures 1 to 4 The combustion apparatus according to an embodiment of the present invention includes a combustion shell 1. The upper surface of the combustion shell 1 is open, and a heat exchanger for supplying hot water (not shown) is provided on the combustion shell 1. A combustion chamber 2 and an air supply chamber 3 below the combustion chamber 2 are provided inside the combustion shell 1. The air supply chamber 3 is separated from the combustion chamber 2 by a partition plate 4.

[0028] In the combustion chamber 2, multiple burners 5, with their longer sides in the front-to-back direction, are arranged side by side in a transverse direction. Each burner 5 has multiple narrow slit-shaped flame holes 51 at intervals in the front-to-back direction at its upper end, and a mixing tube section 53 extending rearward from the inlet 52 at its lower part. Moreover, the mixed gas (a mixture of fuel gas and primary air for combustion) generated in the mixing tube section 53 is ejected from the flame holes 51 and combusted. In addition, a flame rod 13 and an ignition electrode 14 are respectively disposed on the front plate section 11 and the side plate section 12 on the transverse side of the combustion shell 1.

[0029] Air is supplied to the air supply chamber 3 from the fan 6. The fan 6 is a multi-bladed fan with an impeller driven by a motor 62 inside the fan housing 61. A portion of the air supplied to the air supply chamber 3 is supplied to the combustion chamber 2 as secondary air for combustion via multiple distribution holes 41 formed in the partition plate 4. In addition, at the front end of the partition plate 4, there is an upright plate portion 42 that bends upward; and an upper plate portion 43 that bends forward from the upper end of the upright plate portion 42 to reach the front plate portion 11 of the combustion housing 1. As a result, the front portion 31 of the air supply chamber 3 stands upright on the front side of the upright plate portion 42. The front surface of the air supply chamber 3 is blocked by the gas manifold 7. An opening 44 is formed in the upright plate portion 42 facing the inlet 52 of each burner 5. In addition, a nozzle 71 is provided in the gas manifold 7 opposite to each opening 44. Furthermore, fuel gas is supplied from each nozzle 71 toward the inlet 52 of each burner 5, and a portion of the air supplied to the air supply chamber 3 is supplied as primary air for combustion from the front 31 of the air supply chamber 3 toward the inlet 52 of each burner 5.

[0030] Additionally, on the rear wall 32 of the air supply chamber 3 and the transverse side ( Figure 5At least one of the side walls 33 (left side) of the combustion chamber 3 has an air inlet 34 for allowing air from the fan 6 to flow into the air supply chamber 3. In this embodiment, the air inlet 34 is provided on both the rear wall 32 and the lateral side wall 33 of the air supply chamber 3. The fan 6 is positioned higher than the air supply chamber 3 on the outer side of the lateral side of the combustion chamber 1. A channel 8 is provided below the fan 6, extending from the outer side of the lateral side wall 33 of the air supply chamber 3 to the outer side of the rear wall 32 of the air supply chamber 3. (See reference...) Figure 5 A connection port 81 for the fan 6 is provided on the upper surface of channel 8, specifically at the rear position on one lateral side. Furthermore, as... Figure 5 As indicated by the middle arrow a, the air from fan 6 tends to move forward ( Figure 5 (above and middle) and towards the other side laterally ( Figure 5 The gas flows into the supply chamber 3 in a tilted direction (to the right of the middle).

[0031] An impact plate 35 is provided in the air supply chamber 3, which is opposite to the air inlet 34. Using this impact plate 35, a portion of the air flowing in from the air inlet 34 can be directed... Figure 4 As indicated by arrow b, the air bounces towards the air inlet 34. Therefore, due to the influence of the air bouncing towards the air inlet 34 after hitting the thrust plate 35, the air tends to flow towards the distribution holes 41 formed in the portion of the partition plate 4 closer to the air inlet 34. Thus, it is possible to suppress the situation where there is insufficient secondary air in the portion of the combustion chamber 2 closest to the wall where the air inlet 34 is located, that is, in the portion of the combustion chamber 2 closest to the rear wall and the side wall on the lateral side. Furthermore, the upper edge of the thrust plate 35 is positioned above the height of the center portion in the vertical direction of the air inlet 34, so that the air flowing in from the air inlet 34 can be effectively bounced towards the air inlet 34.

[0032] Additionally, the upright plate 35 includes: a first plate portion 351, which faces a portion of an air inlet 34 formed on the rear wall surface 32 of the air supply chamber 3; and a second plate portion 352, which faces a portion of an air inlet 34 formed on the side wall surface 33 on one lateral side of the air supply chamber 3. The other lateral side of the first plate portion 351 ( Figure 5 The end of the right side of the middle plate is located further to the other side than the end of the air inlet 34 opened on the rear wall surface 32 of the air supply chamber 3. The front end of the second plate portion 352 is located further forward than the front end of the air inlet 34 opened on the side wall surface 33 of the side of the air supply chamber 3.

[0033] However, air is difficult to flow into the vicinity of the side wall 33 on the lateral side of the air supply chamber 3, which is adjacent to the front end of the air inlet 34. Therefore, the second plate portion 352 tends to move forward when viewed from above. Figure 5 (above and middle) and towards the horizontal side ( Figure 5 (Left side) tilted. Therefore, as... Figure 5 As indicated by the middle arrow c, air can easily flow from the front end of the second plate portion 352 along the wall portion adjacent to the front end of the air inlet 34 on the side wall 33 of the transverse side of the air supply chamber 3. As a result, air can easily flow into the distribution holes 41 formed in the portion of the partition plate 4 that is closer to this wall portion, thereby making the distribution of secondary air in the combustion chamber 2 more uniform.

[0034] Furthermore, the front end of the second plate portion 352 is located further forward than the front end of the air inlet 34 on the side wall surface 33 on the lateral side of the air supply chamber 3. This allows air to flow more easily along the wall portion adjacent to the front end of the air inlet 34. Additionally, the first plate portion 351 of the upright plate 35 has the following characteristics: it extends from the rear end of the second plate portion 352 towards the other lateral side ( Figure 5 The portion 351a extending forward at an angle from the right side of the middle plate 35, and the portion 351b extending laterally from the end of the portion 351a to the other side, may omit portion 351a, so that the portion extends from the front end of the second plate portion 352 of the upright plate 35. Figure 5 The first plate portion 351 is formed by extending laterally to the other side as shown by the imaginary line in the middle.

[0035] Furthermore, when the fan 6 is positioned higher than the air supply chamber 3 on the outside of the combustion casing 1, and air is supplied to the air inlet 34 via the channel 8 located below the fan 6, the air will bounce upwards on the lower surface of the channel 8 near the air inlet 34. Sometimes, this air will collide with the air bounced from the impact plate 35 at a location below the partition plate 4 near the air inlet 34, thus generating a vortex. Moreover, once a vortex is generated, it will obstruct the airflow into the distribution hole 41 formed in the partition plate 4 near the air inlet 34. In particular, as in this embodiment, when the air inlet 34 is located on both the rear wall 32 and the side wall 33 on the lateral side of the air supply chamber 3, and air from the fan 6 flows into the air supply chamber 3 from the air inlet 34 with a forward-leaning and lateral-leaning component, in the half of the portion of the air inlet 34 located on the rear wall 32 of the air supply chamber 3 near the lateral side, air easily flows into the lower surface portion of the channel 8 near the air inlet 34. Figure 4 It bounces upwards as indicated by the middle arrow d.

[0036] Therefore, in this embodiment, a protective portion 36 is provided, extending from the upper edge of the upper half of the portion of the air inlet 34 opened on the rear wall surface 32 of the air supply chamber 34, near the other side laterally, toward the inside of the air supply chamber 3. Additionally, as... Figure 6 As shown, the portion of the upper edge of the airflow inlet 34 where the protective portion 36 is located is positioned further downwards than the other portions. Additionally, refer to... Figure 5 The length of the protective portion 36 extending inward toward the air supply chamber 3 is set such that, when viewed from below, at least the distribution hole 41 #1, which is closest to the upper edge of the air inlet 34 on which the protective portion 36 is provided, overlaps with the protective portion 36. In this embodiment, in addition to the distribution hole 41 #1, the distribution hole 41 #2, which is second closest to the aforementioned upper edge, also overlaps with the protective portion 36 when viewed from below.

[0037] Accordingly, Figure 4 As shown, the air rebounding upwards from the lower surface portion of the channel 8 near the air inlet 34, as indicated by arrow d, hits the protective portion 36 without colliding with the air rebounding upwards from the upright plate 35, as indicated by arrow b, towards the protective portion 36. As a result, vortices can be suppressed at the location below the portion of the partition plate 4 closest to the air inlet 34. Consequently, air also flows well into the distribution holes 41 (#1 or #2) formed in the portion of the partition plate 4 closest to the air inlet 34, making the distribution of secondary air in the combustion chamber 3 more uniform.

[0038] Alternatively, a protective portion 36 may be formed in a portion further to the lateral side than the half portion of the air inlet 34 opened on the rear wall surface 32 of the air supply chamber 34. However, this would place the protective portion 36 too close to the rear end of the second plate portion 352 of the upright plate 35, resulting in increased ventilation resistance. Therefore, in this embodiment, the protective portion 36 is formed only in the half portion of the air inlet 34 opened on the rear wall surface 32 of the air supply chamber 34, near the lateral side.

[0039] Next, an explanation Figure 7The second embodiment is shown. The basic structure of the second embodiment is not particularly different from that of the first embodiment described above, and the same reference numerals are used for the same components and parts as in the first embodiment. The main difference between the second and first embodiments is that an air inlet 34 is only provided on the rear wall surface 32 of the air supply chamber 3. Furthermore, a horizontally extending, upright plate 35 is provided in the air supply chamber 3, opposite the air inlet 34, which causes a portion of the air flowing in from the air inlet 34 to bounce towards the air inlet 34. Although the upper edge of this upright plate 35 is not shown, it is located, similar to the first embodiment, at a height above the center of the air inlet 34 in the vertical direction. Additionally, the upright plate 35 is inclined rearwards, so that when viewed from above, it approaches the wall surface 32 of the air supply chamber 3 where the air inlet 34 is located from the center of its long side towards each end of its long side. Accordingly, air will easily flow along the portion of the rear wall surface 32 of the air supply chamber 3 adjacent to each of the transverse ends of the air inlet 34, and air will easily flow into the distribution hole 41 formed in the portion of the partition plate 4 closer to the portion of the rear wall surface 32. In addition, according to the second embodiment, although the angle of inclination towards the rearward end of the punch plate 35 from the center of the long side direction is constant, the punch plate 35 can be bent in such a way that the angle of inclination towards the rearward end gradually increases as it approaches the end of the long side direction.

[0040] Additionally, a protective portion 36 is provided, extending from the upper edge of the air inlet 34, including its central portion, toward the inner side of the air supply chamber 3. The length of the protective portion 36 extending toward the inner side of the air supply chamber 3 is set in the same manner as in the first embodiment: at least the #1 distribution hole 41 closest to the upper edge of the air inlet 34 where the protective portion 36 is located, and the #2 distribution hole 41 closest to the aforementioned upper edge portion, overlap with the protective portion 36 when viewed from below. Thus, similar to the first embodiment, air rebounding upwards from the lower surface portion of the channel 8 near the air inlet 34 hits the protective portion 36 without colliding with air rebounding upwards from the upright plate 35 toward the protective portion 36. As a result, vortices can be suppressed at the lower position of the partition plate 4 which is closer to the air inlet 34, so that air can also flow well into the distribution holes 41 of #1 and #2 formed in the partition plate 4 which is closer to the air inlet 34.

[0041] The embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited thereto. For example, a recess or opening may be formed in a part of the impact plate 35 to allow sufficient airflow in front of the impact plate 35. In addition, the present invention is also applicable when an air inlet 34 is provided only on the side wall surface 33 on the lateral side of the air supply chamber 3.

Claims

1. A combustion device comprising a combustion housing, wherein within the combustion housing are: a combustion chamber accommodating a plurality of burners arranged side-by-side in a transverse direction, and an air supply chamber separated from the combustion chamber by a partition plate and located below the combustion chamber. The front surface of the air supply chamber is sealed by a gas manifold used to supply fuel gas to multiple burners. Air supplied to the air supply chamber from the fan is supplied to each burner as primary combustion air from the front of the air supply chamber, and secondary combustion air is supplied to the combustion chamber through multiple distribution holes formed in the partition plate. An air inlet is provided on at least one of the rear wall and the side wall on the lateral side of the air supply chamber to allow air from the fan to flow into the air supply chamber. Its features are, The air supply chamber is equipped with a vertical plate that is opposite to the air inlet and causes a portion of the air flowing in from the air inlet to bounce back towards the air inlet side. The fan is positioned higher than the air supply chamber on the outside of the combustion casing, and air is supplied to the air inlet via a channel located below the fan. It is provided with a protective portion extending from the upper edge of at least a portion of the air inlet toward the inside of the air supply chamber.

2. The combustion device according to claim 1, characterized in that, The air inlet is located on one of the rear wall surface and the side wall surface on the lateral side of the air supply chamber. The upright plate is inclined in such a way that, when viewed from above, it approaches the wall of the air supply chamber with air inlets from the center of the long side toward each end of the long side.

3. The combustion device according to claim 1, characterized in that, The length of the protective part extending toward the inner side of the air supply chamber is set such that, when viewed from below, at least the distribution hole that is closest to the upper edge of the air inlet where the protective part is provided overlaps with the protective part.

4. A combustion device comprising a combustion housing, wherein within the combustion housing are: a combustion chamber accommodating a plurality of burners arranged side-by-side in a transverse direction, and an air supply chamber separated from the combustion chamber by a partition plate and located below the combustion chamber. The front surface of the air supply chamber is sealed by a gas manifold used to supply fuel gas to multiple burners. Air supplied to the air supply chamber from the fan is supplied to each burner as primary combustion air from the front of the air supply chamber, and secondary combustion air is supplied to the combustion chamber through multiple distribution holes formed in the partition plate. An air inlet is provided on at least one of the rear wall and the side wall on the lateral side of the air supply chamber to allow air from the fan to flow into the air supply chamber. Its features are, The air supply chamber is equipped with a vertical plate that is opposite to the air inlet and causes a portion of the air flowing in from the air inlet to bounce back towards the air inlet side. The air inlet is located on the rear wall and the side wall on one side of the air supply chamber. Air from the fan flows into the air supply chamber from the air inlet with a forward-leaning component and a lateral component tilted towards the other side. The ejector plate has: a first plate portion opposite to an air inlet portion formed on the rear wall of the air supply chamber; and a second plate portion opposite to an air inlet portion formed on the side wall of the air supply chamber on one side of the lateral direction, and inclined forward and to the lateral direction when viewed from above. The fan is positioned higher than the air supply chamber on the outside of the combustion casing, and air is supplied to the air inlet via a channel located below the fan. The air supply chamber is provided with a protective portion extending toward the inside of the air supply chamber from the upper edge of at least half of the portion of the air inlet that is opened on the rear wall of the air supply chamber.

5. The combustion device according to claim 4, characterized in that, The length of the protective part extending toward the inner side of the air supply chamber is set such that, when viewed from below, at least the distribution hole that is closest to the upper edge of the air inlet where the protective part is provided overlaps with the protective part.

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