JP2012017905A - Combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a latent heat recovery type combustion device employing a reverse combustion system, having a low flow passage resistance, and having low overall height.SOLUTION: This combustion device includes a combustion can body section 3, and an exhaust flow passage forming section 6 disposed upright in parallel with the combustion can body section 3. The lower portion of the combustion can body section 3 and the lower portion of the exhaust flow passage forming section 6 are connected to each other through a communication passage forming section. The communication passage forming section functions as a secondary heat exchanger 5 constituted of a case member 20 and a pipe line member 21. The pipe line member 21 is an annular heat exchanging flow passage provided with five heat receiving tubes 31, a water inlet-side header 50, and a water outlet-side header 51. The heat receiving tubes 31 of the pipe line member 21 are broadly divided into a loop section 55 and an inlet/outlet pipe section 56. The inside of the case member 20 is divided into a loop section storage area (a main portion storage area) 66 and an inlet/outlet pipe arrangement area (a cavity forming area) 88.

Description

  The present invention relates to a latent heat recovery type combustion apparatus. In particular, the present invention relates to a latent heat recovery type combustion apparatus employing a reverse combustion system.

Combustion apparatuses that not only recover sensible heat contained in combustion gas but also recover latent heat are known. A combustion apparatus capable of recovering sensible heat and latent heat is called a latent heat recovery type combustion apparatus.
Here, the latent heat is the heat of condensation of water vapor contained in the combustion gas. Accordingly, when the latent heat is recovered, water vapor in the combustion gas is condensed and drainage is generated. This drain is acidic.
Therefore, in the latent heat recovery type combustion apparatus, a heat exchanger for recovering sensible heat and a heat exchanger for recovering latent heat are individually mounted to cope with drainage.
The former heat exchanger that recovers sensible heat is called a primary heat exchanger. On the other hand, the latter heat exchanger that recovers latent heat is called a secondary heat exchanger.

  It is recommended that the secondary heat exchanger that recovers latent heat be made of bare pipe without fins in the water pipe in order to promote drainage. Also, it is recommended to use a material such as stainless steel so that it does not corrode with acidic drain.

  Therefore, in the latent heat recovery combustion apparatus, a heat exchanger having a structure in which a plurality of bare tubes are connected in parallel between a pair of headers as in Patent Document 1 is employed. In the heat exchanger disclosed in Patent Document 1, the headers are provided at positions facing each other, and a plurality of straight water pipes (bare pipes) communicate with each other between the headers. In the heat exchanger disclosed in Patent Document 1, all the water tubes (bare tubes) are straight.

  Although the heat exchanger disclosed in Patent Document 1 has excellent heat exchange efficiency, there is a problem that it takes time to assemble. That is, in the heat exchanger disclosed in Patent Document 1, it is necessary to weld a large number of water pipes to the header, requiring skill in production, and improvement has been desired.

Therefore, the present applicant solved this problem by bending the water pipe into a loop shape to form a spiral (Patent Documents 2, 3, and 4).
FIG. 22 is a front view and a plan view of the heat exchanger disclosed in Patent Document 2. The basic structure of the heat exchanger is the same for other documents.
In the heat exchanger 100 disclosed in Patent Document 2, a plurality of water pipes 101 are arranged in parallel on the same horizontal plane, and the water pipes 101 are bent into a loop shape to form a spiral having an elliptical planar shape.

That is, the heat exchanger disclosed in Patent Document 2 includes a case member 102 and a pipe member 103. The pipe member 103 has a water inlet side header 105 and a water outlet side header 106. The two headers 105 and 106 are both arranged outside the same side of the case member 102.
Five water pipes 101 are connected between the two headers 105 and 106.
The water pipes 101 of the headers 105 and 106 are both arranged substantially horizontally and in parallel, and constitute an elliptical loop while maintaining this state. Further, the water pipe 103 of the pipe line member 103 forms a spiral, and each loop has seven stages.

In the heat exchanger 100 disclosed in Patent Literature 2, the loop portion 110 of the pipe member 103 extends over the entire area of the case member 102.
That is, in the heat exchanger 100 disclosed in Patent Document 2, the loop portion 110 has two arc portion regions 111 and 112, and a linear region 113 is between them. The outermost positions of the arc regions 111 and 112 at both ends are positions close to the side walls 115 and 116 of the case member 102.

By the way, there exists a form called a reverse combustion system as one form of a combustion apparatus.
In the reverse combustion method, the burner is disposed downward. FIG. 23 shows a layout of a typical reverse combustion type combustion apparatus.
In the combustion apparatus 200 of the reverse combustion type, as shown in FIG. 23, a combustion can body portion 202 to which a burner 201 is connected, and an exhaust flow path forming portion 203 that is erected in parallel with the combustion can body portion 202, have.
The lower part of the combustion can body part 202 and the lower part of the exhaust flow path forming part 203 are connected by a communication path forming part 205.

Patent Document 5 discloses an example in which the heat exchanger 100 having the loop portion 101 described above is employed in the reverse combustion type combustion apparatus 200.
In the combustion apparatus 200 disclosed in Patent Document 5, a primary heat exchanger 210 that recovers sensible heat of the combustion can body 202 is provided. The exhaust flow path forming unit 203 includes a silencer.
And the communication path formation part 205 which connects both is made with the heat exchanger 100 mentioned above.
That is, in the combustion apparatus 200 disclosed in Patent Document 5, the communication passage forming portion 205 is the heat exchanger 100 itself, and the combustion can body portion 202 and the exhaust passage are disposed on the heat exchanger 100 (communication passage forming portion 205). The forming unit 203 is placed side by side.

Japanese Patent Laid-Open No. 2005-274043 JP 2008-32252 A JP 2009-8287 A JP 2007-333343 A JP 2010-7968 A

When the heat exchanger 100 disclosed in Patent Documents 2, 3, and 4 is applied to the reverse combustion type combustion apparatus 200, there is a problem that the exhaust resistance of the heat exchanger 100 increases.
That is, when the heat exchanger 100 is applied to the reverse combustion type combustion apparatus 200, the combustion can body portion 202 and the exhaust flow passage formation portion 203 are arranged on the heat exchanger 100 (communication passage forming portion 205) as described above. Will be placed.
When the positional relationship between the combustion can body portion 202 and the exhaust flow path forming portion 203 at this time and the case member 102 and the pipe line member 103 of the heat exchanger 100 is observed from the upper side, a state as shown in FIG. 24 is obtained.
As apparent from FIG. 24, when the heat exchanger 100 is applied to the reverse combustion type combustion apparatus 200, the combustion can body portion 202 and the exhaust flow path forming portion 203 are placed on the left and right loop portions 111 and 112. Here, there is a problem that the combustion can body portion 202 is mounted on the loop portion 111 on the left side of the drawing.
That is, when the heat exchanger 100 disclosed in Patent Documents 2, 3, and 4 is applied to the combustion apparatus 200 of the reverse combustion type, the loop portion 111 exists in the lower portion of the combustion can body portion 202, and the combustion can body portion 202. The loop portion 111 blocks the exhaust flow path.
For this reason, the loop part 111 becomes a barrier and the combustion gas generated in the combustion can body part 202 is inhibited from being introduced into the heat exchanger 100.

  For this reason, if the heat exchanger 100 is applied to the combustion apparatus 200 of the reverse combustion type, the exhaust resistance of the heat exchanger 100 is increased, and a high-pressure blower corresponding to this must be mounted.

Further, if the combustion gas is intensively introduced into the heat exchanger 100 from the gap 117 formed in the center of the loop of the pipe member 103, the increase in exhaust resistance is reduced, but this configuration is adopted. For this purpose, it is necessary to separately provide a flow path forming member for guiding the combustion gas generated in the combustion can body portion 202 to the gap 117 formed in the center of the loop.
That is, as shown in FIG. 25, the flow path forming member 205 must be interposed between the combustion can body 202 and the heat exchanger 100. As a result, the overall height of the combustion device 200 increases, and the outer shape of the combustion device 200 increases.

  Accordingly, the present invention focuses on the above-described problems of the prior art, and an object thereof is to develop a combustion apparatus having low exhaust resistance and low overall height.

  The invention according to claim 1 for solving the above-described problem is a combustion can body portion that generates combustion gas and allows the combustion gas to pass downward in the vertical direction, and is arranged in parallel with the combustion can body portion. An exhaust flow path forming section provided, and a communication path forming section connecting the combustion can body section and the exhaust flow path forming section, and forming the combustion can body section and the exhaust flow path on the communication path forming section. In the combustion apparatus in which the communication passage forming portion includes a heat exchange pipe member, the communication passage forming portion has a case member, and the case member introduces a gas that communicates with the combustion can body portion. And a gas exhaust port communicating with the exhaust flow path forming portion, and the case member has a main portion containing area in which a main portion of the pipe member is disposed, and substantially the main portion containing area. There is a cavity forming region adjacent to the same height, and the cavity is located immediately below the gas inlet. A combustion apparatus characterized in that there is a gas generating region, an upper part of the main part containing area or an upper part in the vicinity of the main part containing area has a gas exhaust port, and an upper part of the main part containing area has an exhaust passage forming part. .

The combustion apparatus of the present invention includes a combustion can body that generates combustion gas and allows the combustion gas to pass downward in the vertical direction, and is a reverse combustion type combustion apparatus.
In the combustion apparatus of the present invention, a pipe member for heat exchange is built in the communication path forming portion. That is, in the combustion apparatus of the present invention, the communication path forming portion functions as a secondary heat exchanger.
As for the communicating path formation part employ | adopted with the combustion apparatus of this invention, a case member has a gas inlet and a gas outlet. Further, the inside of the case member is divided into a main part accommodating region and a cavity forming region, and there is a cavity forming region at a position directly below the gas inlet. Combustion gas can be directly introduced into the cavity forming region from the combustion can body. Since the cavity forming area has a space, there are few obstacles when introducing the combustion gas and the like, and the flow path resistance is small.

  In the invention according to claim 2, the pipe member includes a loop part as a main part, an inlet side pipe part for introducing the heat receiving body into the loop part, and an outlet side pipe part for discharging the heat receiving body from the loop part. 2. The apparatus according to claim 1, wherein the loop portion is disposed in a main portion accommodating region, and the inlet side tube portion and the outlet side tube portion are disposed in a cavity forming region. It is a combustion device.

  According to the configuration of the present invention, the cavity forming region can be formed without difficulty, and the inside of the case member can be divided into the cavity forming region and the main portion accommodating region.

  In the invention according to claim 3, the pipe member is provided with a plurality of pipes arranged in parallel, the loop portion is wound in a plurality of stages, and the inlet side pipe part and the outlet side pipe part are the plurality of stages. Is connected to the uppermost and lowermost stages, and the inlet side pipe part and the outlet side pipe part are at different heights, and the upper side of the inlet side pipe part and the outlet side pipe part located on the lower side 3. The combustion apparatus according to claim 1, wherein a partition member that partially partitions the main portion housing region and the cavity forming region is provided.

In the present invention, since the pipe member is a plurality of pipes arranged in parallel, heat exchange can be performed by passing a heat receiving body having a large flow rate.
The loop portion is wound in a plurality of stages. That is, it has a spiral shape. Therefore, each pipe is long and the heat exchange efficiency is high.
Further, since the inlet side pipe part and the outlet side pipe part are on different planes, a space having a horizontal spread between any one of the upper side pipe line and the lower side pipe line or the bottom surface of the case member, etc. Is formed. Therefore, the combustion gas or the like that has entered the inlet / outlet pipe arrangement region flows in the horizontal direction, and contacts with each part of the pipe member to advance heat exchange.
Furthermore, in the combustion apparatus of the present invention, a partition member is provided, and this partition member partially closes the space between the main part accommodating region and the cavity forming region. That is, it does not completely block between the two, but only a part is blocked. Therefore, the combustion gas or the like that has entered the cavity forming region enters the main portion accommodating region from a desired introduction portion, and heat exchange proceeds.

  The combustion apparatus of the present invention has low exhaust resistance. Therefore, a small blower is sufficient. The combustion apparatus of the present invention has a low overall height and a small outer shape.

It is a front view of the combustion apparatus of the embodiment of the present invention. It is a perspective view of the heat exchanger (communication path formation part) employ | adopted with the combustion apparatus of embodiment of this invention. It is a top view of the heat exchanger of FIG. It is a disassembled perspective view of the heat exchanger of FIG. (A) (b) (c) (d) is a perspective view of the top plate which shows the formation process of the top plate of the heat exchanger of FIG. It is the perspective view of the heat exchanger which observed the heat exchanger of FIG. 2 from the back side. It is the top view of the heat exchanger in the state which removed the top plate from the state of FIG. 3, and its partially expanded view. FIG. 8 is an enlarged view of a region A in FIG. 7. It is a BB cross-sectional enlarged view of FIG. It is the perspective view which observed the gas introduction part vicinity of the heat exchanger of FIG. 2 from a different angle. It is the fragmentary perspective view explaining the condition at the time of inserting a spacer in a pipe line member, and the enlarged view of a spacer. It is a fragmentary perspective view in the state where a spacer was inserted in a pipe line member. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a perspective view of the heat exchanger of FIG. 2 which added the flow of the combustion gas with the arrow. It is an AA cross-section perspective view of FIG. It is a perspective view explaining the flow of the combustion gas in a loop part accommodation area | region (main part accommodation area | region). It is a perspective view which shows the modification of a pipe line member. It is a perspective view which shows the other modification of a pipe line member. It is sectional drawing which shows the modification of a case member. It is a front view which shows the modification of a heat exchanger (communication path formation part). (A) is front sectional drawing of the heat exchanger of a prior art, (b) is a top view of the same heat exchanger. It is explanatory drawing which shows the basic layout of the combustion apparatus of a reverse combustion system. (A) (b) is explanatory drawing explaining the positional relationship of the combustion can body part and exhaust flow path formation part of the heat exchanger of FIG. It is explanatory drawing explaining the layout of the combustion apparatus of a prior art.

Embodiments of the present invention will be further described below.
The combustion apparatus 1 of the present embodiment is specifically a hot water supply apparatus, and is a so-called latent heat recovery type combustion apparatus that includes a burner section 2, a primary heat exchanger 8, and a secondary heat exchanger 5. . The basic layout of the combustion apparatus 1 is the same as that of the prior art, and the combustion can body portion 3 to which the burner portion 2 is connected, and the exhaust flow path erected in parallel with the combustion can body portion 3. And a forming portion 6.
And the lower part of the combustion can body part 3 and the lower parts of the exhaust flow path forming part 6 are connected to each other through the secondary heat exchanger 5. That is, in the combustion apparatus 1 of the present embodiment, the secondary heat exchanger 5 also functions as a communication path forming unit.
That is, the combustion can body portion 3 and the exhaust flow path forming portion 6 communicate with the secondary heat exchanger 5 provided on the bottom side of the combustion device 1. For this reason, the combustion apparatus 1 is formed with a space communicating from the combustion can body portion 3 through the secondary heat exchanger 5 to the exhaust flow path forming portion 6 so that the cross-sectional shape is substantially “U” shape. Yes.

  The burner part 2 and the combustion can body part 3 are so-called reverse combustion type combustion parts, and form a flame downward. The burner unit 2 is provided with a fuel spray nozzle, a combustion cylinder, and the like (not shown) in the same manner as known ones. In addition, a blower 11 is provided on the upper part of the burner unit 2. By operating the blower 11, combustion air is introduced into the burner unit 2 and the combustion can body unit 3, and a fuel supply source (not shown) is provided. The liquid fuel supplied from is sprayed downward from a fuel spray nozzle (not shown) to generate a flame inside the combustion can body portion 3.

  That is, the combustion can body part 3 is disposed below the burner part 2 and functions as a combustion gas passage through which the high-temperature combustion gas generated by the combustion operation in the burner part 2 passes downward.

  A primary heat exchanger 8 is provided at a lower end side portion of the combustion can body portion 3. The primary heat exchanger 8 is for mainly recovering sensible heat contained in the combustion gas flowing through the combustion can body part 3. The primary heat exchanger 8 is a so-called fin-and-tube heat exchanger.

  The exhaust flow path forming part 6 has a labyrinth fuel gas flow path inside and functions as a silencer. A gas discharge part 15 for discharging the combustion gas to the outside is provided above the exhaust flow path forming part 6.

The secondary heat exchanger 5 is a box-shaped member disposed below the combustion can body portion 3 and is a portion that directly communicates with both the combustion can body portion 3 and the exhaust flow path forming portion 6. As described above, in the present embodiment, the secondary heat exchanger 5 also functions as a communication path forming unit.
That is, the secondary heat exchanger 5 has an internal space extending in the width direction of the combustion device 1 (left and right direction in FIG. 1). The secondary heat exchanger 5 is also in communication with an exhaust flow path forming unit 6 disposed on the side of the combustion can body unit 3. For this reason, the secondary heat exchanger 5 functions as a portion that allows the combustion gas flowing downward in the combustion can body portion 3 to flow in and flows out the combustion gas toward the exhaust flow path forming portion 6. That is, the secondary heat exchanger 5 functions as a portion for turning upward the flow direction of the combustion gas flowing downward.

Hereinafter, the structure of the secondary heat exchanger 5 which is a feature of the present embodiment will be described.
As shown in FIGS. 2, 3, and 4, the secondary heat exchanger 5 includes a case member 20 and a pipe member 21.
Furthermore, the case member 20 is a rectangular box constituted by a case main body 22, a top plate member (plate member) 23, and a part of the pipe line member 21.

The case body 22 is made of a material resistant to rust such as stainless steel, and includes a bottom plate portion 25 and three peripheral wall portions 26, 27, and 28. The bottom plate portion 25 is rectangular in plan view. The bottom plate portion 25 is provided with a gentle slope (not shown) for collecting drain. The bottom plate portion 25 is provided with a groove (not shown) for guiding the drain. Further, a pipe 30 for draining is connected to the bottom plate portion 25.
The peripheral wall portions 26 and 28 form a peripheral wall on the long side of the case member 22. On the other hand, the peripheral wall portion 27 is located between the peripheral wall portions 26 and 28 described above, and forms a peripheral wall on one short side of the case member 22.

  In the vicinity of the center of the case body 22 in the longitudinal direction and on one long side, a shielding wall member 38 having a “U” shape in front view is provided. The shielding wall member 38 includes a header side wall 95, a central wall 96, and a loop side wall 97 that are connected at right angles. Here, the header side wall 95 and the loop side wall 97 are both parallel to the peripheral wall portion 27 on the short side of the case member 20, and the peripheral wall portion 28 on the long side is an end portion in the vertical direction in plan view from the peripheral wall portion 28. It extends. The central wall 96 connects the header side wall 95 and the loop side wall 97, and is disposed in parallel with the peripheral wall portion 27 on the long side.

A rib 36 as shown in FIGS. 4, 6, 7, and 8 is formed on the peripheral wall portion 26 on the back side in FIG. 4. The rib 36 is formed by drawing a part of the peripheral wall portion 26, and is a protruding portion that protrudes toward the inside of the case main body 22. Moreover, the rib (protrusion part) 36 is continuously extended in the vertical direction.
In this embodiment, the rib 36 is provided only in one place only on the peripheral wall portion 26 on the back side in FIG.

The top plate member (plate member) 23 is a substantially rectangular plate provided with a gas inlet 33 and a gas outlet 35.
The gas inlet 33 provided in the top plate member (plate member) 23 has a rectangular shape and is a large one that occupies about 30 to 40 percent of the total area of the top plate member (plate member) 23. The gas inlet 33 is provided at a position near one short side of the top plate member (plate member) 23. More specifically, the gas introduction port 33 is formed at a position close to the water inlet side header 50 and the water outlet side header 51 side of the pipe line member 21 to be described later.

A part of the open end of the gas inlet 33 is bent downward. The bent portion functions as the partition member 40. The partition member 40 is located between the gas inlet 33 and the gas outlet 35.
Further, one of the side sides of the partition member 40 (side facing the top and bottom direction) is bent in a direction away from the headers 50 and 51 to form a secondary bent portion 41. The secondary bending portion 41 is provided on the side closer to the center of the two side edges of the partition member 40 (side toward the top-and-bottom direction with respect to the use state). It is bent toward the loop 55 side.

The gas discharge port 35 is a rectangular opening, and its area is smaller than that of the gas introduction port 33 described above.
The gas discharge port 35 is formed at a position away from the headers 50 and 51 of the pipe line member 21 to be described later. Further, the gas outlet 35 is located at one long side 37. That is, the gas discharge port 35 is provided at a position close to the peripheral wall portion 28 facing the rib (projecting portion) 36 of the case main body 22 described above.

Assuming that the case member 20 is divided into four sections by two center lines X and Y as shown in FIG. 1, FIG. 2, FIG. 3 and FIG. 5C, the left side of the drawing (the inlet side header 50 and the outlet side header 51). Side) and the front side (water discharge side header 51 side) is defined as a zone, and is defined as b zone, c zone, and d zone in the clockwise direction. The ribs 36 described above are provided on the c section side.
The relationship between the combustion can body portion 3 and the exhaust flow path forming portion 6 will be described. As shown in FIG. 1, the combustion can body portion 3 is mainly placed on the a section and the b section on the left side of the drawing. The exhaust flow path forming part 6 is placed on the c section and the d section on the right side.

When the case member 20 is divided into four sections (a, b, c, d) in accordance with the above-described definition, the gas introduction port 33 is at a position straddling the a section and the b section. Moreover, the partition member 40 exists in a section. The secondary bending part 41 of the partition member 40 is bent at about 90 degrees from the a section toward the d section.
Moreover, the gas exhaust port 35 will be located in d division.

In addition, it is recommended that the top plate member (plate member) 23 employed in this embodiment is made by punching a flat plate and then bending it.
That is, as shown in FIG. 5A, a flat plate material 43 is prepared, and a portion indicated by a broken line is punched out. Here, the punching shape at the position corresponding to the gas introduction port 33 is a shape having a small square cutout portion 46 in a part of the large square 45 as shown in FIG. However, there is a cut line 49 at the base portion of the notch 46 and on the center side.
As a result, as shown in FIG. 5 (b), an opening 48 is formed in the a section and at a position away from the header 50, 51 side of the duct member 21, leaving the square plate piece 47 in a cantilever shape. .
Thereafter, one side of the square plate piece 47 is bent downward as shown in FIG. That is, the part of the cut line 49 is bent downward. The bent portion becomes the secondary bent portion 41.

Further, as shown in FIG. 5D, the cantilevered plate piece 47 is bent vertically to the lower side of the drawing (inside the case member 20). As a result, a gas inlet 33 that is a square opening is formed, and a structure in which the partition member 40 hangs down on one side thereof is completed.
Further, one side of the partition member 40 is bent to form a secondary bent portion 41, and the secondary bent portion 41 faces in the direction of the X axis.

Next, the pipe member 21 will be described.
As shown in FIGS. 3, 4, and the like, the pipe line member 21 is an annular heat exchange provided with a plurality of (in this embodiment, five) heat receiving pipes 31, a water inlet header 50, and a water outlet header 51. It is a flow path. Further, the pipe member 21 is provided with a wall surface member 52 constituting a wall surface of the end side of the case member 20.

If it demonstrates sequentially, the inflow side header 50 will be connected to the one end side of each heat receiving pipe 31, and the outflow side header 51 will be connected to the other end side. The heat receiving pipe 31 is formed of a pipe having excellent heat conductivity and a smooth surface. That is, the heat receiving pipe 31 is a so-called bare pipe. The heat receiving tubes 31 are arranged in parallel with a certain interval.
Each heat receiving pipe 31 of the pipe line member 21 is largely divided into a loop part 55 and an entrance / exit pipe part 56.
The loop part 55 is a part that constitutes an elliptical loop in plan view, and has a helical structure, with the elliptical part overlapping in five steps.
Between each stage of the loop portion 55, there is a gap 24 as shown in FIGS.

That is, the loop part 55 is formed in a spiral shape including straight portions 57 and 58 extending straight in a certain direction and curved (arc-shaped) curved portions 59 and 60 alternately.
The loops of the heat receiving tubes 31 are wound concentrically while maintaining a parallel state. Therefore, the inner heat receiving pipe 31 has a shorter overall length than the outer heat receiving pipe 31.

On the other hand, the entrance / exit pipe portion 56 is linear.
That is, each heat receiving pipe 31 that is extended from the water inlet side header 50 in the horizontal direction and in parallel functions as the inlet side pipe portion 61 and reaches the straight portion 57 of the uppermost loop 62.
And the terminal part of the loop 63 of the lowest step is extended linearly, and the output side pipe part 65 is formed. That is, the straight portion 58 of the lowermost loop 63 is extended as it is to constitute the outlet side pipe portion 65.
A water discharge side header 51 is connected to the end of the discharge side pipe portion 65.

The above-described inlet side pipe part 61 and outlet side pipe part 65 are both horizontal when used, and a plane including a bundle of heat receiving pipes 31 constituting the inlet side pipe part 61, and an outlet side pipe part. The plane including the 65 heat receiving tubes 31 is parallel.
However, since the inlet side pipe part 61 is connected to the uppermost loop 62 and the outlet side pipe part 65 is drawn from the lowermost stage, the inlet side pipe part 61 and the outlet side pipe part 65 are not high and low. There is a difference. That is, the inlet side pipe part 61 is in the upper part and the outlet side pipe part 65 is in the lower part.

  Further, when the positional relationship between the inlet side pipe part 61 and the outlet side pipe part 65 is observed in plan view, the inlet side pipe part 61 and the outlet side pipe part 65 are connected to the linear portions 57 and 58 facing the loops 62 and 63, respectively. Therefore, they are in a position separated in the horizontal direction.

The wall surface member 52 is inserted with an inlet side pipe part 61 and an outlet side pipe part 65.
When the length L1 from the wall surface member 52 to the loop portion 55 is compared with the major axis L2 of the ellipse that constitutes the loop portion 55, they are substantially equal in length. The length L1 from the wall surface member 52 to the loop portion 55 is preferably in the range of 20 percent to 150 percent of the major diameter L2 of the loop portion 55. That is, if the length L1 from the wall surface member 52 to the loop portion 55 is excessively small, the size of the cavity 80 described later becomes small and the flow path resistance increases. Conversely, if L1 is too large, the length of the heat receiving pipe 31 that contributes to heat exchange is shortened, and the heat exchange efficiency is reduced.

In addition, a spacer 67 is interposed in one linear portion 58 of the loop portion 55 in order to maintain the interval between the steps.
As shown in FIG. 11, the spacer 67 is formed by bending a single wire.
Each of the spacers 67 is composed of an outgoing line 72 and a return line 73, and upper and lower stages are connected by curved portions 68a, b, c, d, and e in a vertical posture.
That is, the uppermost step portion has an uppermost portion going line 72a extending from the end of the line on the drawing front side to the back of the drawing, and the leading end of the uppermost portion going line 72a is connected to the curved portion 71a in the horizontal posture. The horizontal posture curve portion 71a is connected to the uppermost step return line 73a. The uppermost part line 72a and the uppermost part return line 73a are at the same height, based on the posture in use, and the uppermost part line 72a, the curved part 71a, and the uppermost part return line 73a. Forms the uppermost step.

  Furthermore, the tip of the uppermost step return line 73a is connected to the curved portion 68a in the vertical posture, and the tip is further connected to the second step line 72b. Here, the second-stage line 72b is located directly below the uppermost-stage return line 73a, based on the posture in use.

The tip of the second step line 72b is connected to the curved portion 71b in the horizontal posture, and the tip is connected to the second step return line 73b.
Here, the second-stage return line 73b is located at the same height as the second-stage going line 72b and at a position just below the uppermost-stage going line 72a, based on the posture in use. Therefore, the second step line is formed by the second step line 72b, the curved portion 71b, and the second step return line 73b.
In this way, the outgoing line 72a, b, c, d, e, f of each step, the curved portion 71a, b, c, d, e, f of the horizontal posture and the return line 73a, b, c, d, e, f The steps to be configured are connected by the curved portions 68a, b, c, d, and e in the vertical posture on the front side of the drawing to form six steps.
Each step portion is connected by curved portions 68a, b, c, d, e in a vertical posture provided in the column on the front side of the drawing, and the other column side is connected between the steps. There are no parts. Therefore, the spacer 67 can be inserted into the loop portion 55 starting from the side where the curved portions 68a, b, c, d, e in the vertical posture do not exist.

  As a result, as shown in FIG. 14, between the stages formed by the heat receiving pipe 31 of the loop portion 55, the outgoing lines 72a, b, c, d, e and the curved portions 71a, b, c, A step of a spacer 67 composed of d, e and return lines 73a, b, c, d, e is inserted.

  On the other hand, in the portion where the spacer 67 is not provided, as shown in FIG. 13, a predetermined gap 24 is maintained between the stages formed by the heat receiving pipe 31 of the loop portion 55.

Next, the positional relationship between the components of the secondary heat exchanger 5 will be described.
Most of the pipe member 21 described above is accommodated in the case member 20.
That is, the case main body 22, the top plate member (plate member) 23, and the wall surface member 52 of the pipe member 21 are combined to form a rectangular parallelepiped case member 20. The top plate member (plate member) 23 is a member that constitutes a surface that faces the flat surface 77 that constitutes the loop portion 55 of the pipe line member 21.
All portions of the pipe member 21 from the wall surface member 52 to the distal end side (the loop portion 55 side) are accommodated in the case main body 22.
In other words, the water inlet header 50 and the water outlet header 51 are outside the case member 20.

As described above, each heat receiving pipe 31 of the pipe line member 21 is largely divided into the loop part 55 and the entrance / exit pipe part 56, and the length L 1 from the wall surface member 52 to the loop part 55 and the loop part 55 are configured. Since the major axis L2 of the ellipse is substantially equal, when the case member 20 is viewed in plan, it is divided into a loop portion accommodating region (main portion accommodating region) 66 and an inlet / outlet pipe arrangement region (cavity forming region) 88 in the longitudinal direction. That is, the loop portion 55 does not exist in the inlet / outlet pipe arrangement region 88, and only the inlet side pipe portion 61 and the outlet side pipe portion 65 exist.
In this embodiment, the ratio of the loop portion accommodation area 66 and the inlet / outlet pipe arrangement area 88 is substantially the same, but the loop part accommodation area 66 is desirably at least 20 percent of the inlet / outlet pipe arrangement area 88. Further, the loop portion accommodation area 66 is desirably 150% or less of the inlet / outlet pipe arrangement area 88.

  If it demonstrates based on an above-described division, most of a division and b division will be the inlet / outlet pipe arrangement | positioning area | region 88, and most of c division and d division will be the loop part accommodation area | region 66. FIG.

Further, the gas inlet 33 provided in the case member 20 is open to the inlet / outlet pipe arrangement region 88. The partition member 40 provided at the opening end of the gas introduction port 33 is positioned on the outlet side pipe portion 65. Therefore, the partition member 40 partially shields between the inlet / outlet pipe arrangement region 88 and the loop portion accommodation region 66. It can be said that the partition member 40 covers one curved (arc-shaped) curved portion 60 of the loop portion 55.
The secondary bent portion 41 of the partition member 40 is bent toward the loop portion 55. The secondary bending part 41 functions as a wind direction plate. The tip of the secondary bending portion 41 is in the vicinity of the loop portion 55. There is an interval of about 2 mm to 10 mm between the tip of the secondary bending portion 41 and the loop portion 55.

Further, a shielding wall member 38 of the case body 22 is provided between the gas inlet 33 and the gas outlet 35. More specifically, there is a shielding wall member 38 between the partition member 40 and the gas discharge port 35.
As described above, the gas inlet 33 is open to the inlet / outlet pipe arrangement region 88. In the inlet / outlet pipe arrangement region 88, the bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe portion 61 extends in a band shape on the heaven region improvement side. That is, the bundle 75 of the heat receiving tubes 31 extends in a belt shape at a position near the peripheral wall portion 26 that constitutes one long side on the Tenchi region improvement side.
On the other hand, the bundle 76 of the heat receiving pipes 31 constituting the outlet side pipe portion 65 extends in a strip shape on the lower side in the vertical direction.
That is, the bundle 76 of the heat receiving tubes 31 extends in a band shape at a position near the peripheral wall portion 28 that constitutes the other long side on the lower side in the vertical direction.

Since there is a large drop between the bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe part 61 and the bundle 76 of the heat receiving pipes 31 constituting the outlet side pipe part 65, it is directly below the gas inlet 33. A wide cavity portion (first cavity portion) 80 is present at the position as shown in FIGS. 2, 15, and 16.
A part of the portion in the b section of the gas inlet 33 has a bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe section 61 at a position slightly below the opening. Therefore, a part of the portion in the b section in the gas introduction port 33 is substantially closed by the bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe part 61. However, as described above, the portion in the a section in the gas inlet 33 does not have a member that closes it.

When the eyes are moved into the case main body 22, the bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe portion 61 is arranged in a band shape at the upper part of the b section as described above. It is hollow. That is, the second cavity 83 is provided under the heat receiving pipe 31 of the b section. The second cavity 83 communicates directly with the first cavity 80 described above.
Further, as described above, the partition member 40 is located on the outlet side pipe portion 65 and does not exist on the inlet side pipe portion 61 side. Further, the shielding wall member 38 is provided with the peripheral wall portion 28 on the long side on the outlet side pipe portion 65 side as an end portion, and does not reach the inlet side tube portion 61 side.
Therefore, there is an opening 81 in a portion other than the partition member 40. The second cavity portion 83 communicates with the loop portion accommodation region 66 side through the opening 81. That is, the b section and the c section communicate with each other.

As described above, the peripheral wall 26 constituting one long side of the inner surface of the case member 22 has the rib 36, and the tip of the rib 36 abuts against the linear portion 57 of the loop portion 55 of the pipe member 21. Yes. Therefore, a predetermined gap 78 is secured between the other portion of the pipe member 21 and the peripheral wall portion 26 of the case member 22 (FIG. 7).
The gap 78 is small, specifically about 1 mm to 5 mm, more preferably 2 to 3 mm.
Further, a larger gap 79 is present between the peripheral wall portion 27 on the short side and the pipe member 21. The size of the gap 79 is about 1 cm to 5 cm, and more preferably 2 cm to 3 cm.
Further, there is a larger gap between the peripheral wall 28 on the other long side and the pipe member 21.

  As described above, the spacer 67 is attached to one linear portion 58 of the loop portion 55. The attachment position of the spacer 67 is between the gas inlet 33 and the gas outlet 35 as shown in FIGS. is there. More specifically, it is on the straight line 82 (FIGS. 2 and 10) that connects the gas discharge port 35 and the opening portion 81 that is in the immediate vicinity of the gas discharge port 35 and is not sealed by the partition member 40.

  As described above, in the combustion apparatus 1 of the present embodiment, the combustion can body portion 3 and the exhaust flow path forming portion 6 are placed on the secondary heat exchanger 5. More specifically, as shown in FIG. 1, the combustion can body portion 3 is placed on the left a section and the b section of the secondary heat exchanger 5. Further, the exhaust flow path forming unit 6 is placed on the c section and the d section on the right side.

  Therefore, the end portion of the combustion can body 3 covers the gas inlets 33 provided in the a section and the b section. Similarly, the starting end portion of the exhaust flow path forming portion 6 covers the gas discharge ports 35 provided in the c section and the d section.

Next, the function of the combustion apparatus 1 of this embodiment is demonstrated.
The water inlet side header 50 and the water outlet side header 51 are disposed outside the case member 20 and on the side (left side in front view in FIGS. 2 and 3). The incoming water header 50 is disposed above and in front of the outgoing water header 51. The water inlet header 50 is supplied with water through a pipe (not shown). The water supplied from the water supply source branches to the plurality of heat receiving pipes 31 and flows in parallel, and is discharged from the water discharge side header 51.
Further, the water discharge side header 51 is connected to the primary heat exchanger 8 by a pipe (not shown), and the water discharged from the water discharge side header 51 flows through the primary heat exchanger 8.

  In the combustion apparatus 1, when the burner unit 2 starts the combustion operation, the combustion gas generated along with the combustion operation of the burner unit 2 flows downward in the combustion can body unit 3.

Thereafter, the combustion gas that has passed through the combustion can body 3 is introduced into the case member 20 of the secondary heat exchanger 5 from the gas inlet 33 as shown by the arrow in FIG.
As shown by arrows A and B in FIGS. 15 and 16, the approach direction of the combustion gas is a direction perpendicular to the plane 77 constituting the loop portion 55.
Of the combustion gases introduced into the case member 20 of the secondary heat exchanger 5, the combustion gas that has entered from the section b immediately becomes a bundle 75 of the heat receiving tubes 31 constituting the inlet side pipe portion 61 as indicated by an arrow A. Clash with. That is, as described above, a part of the portion in the b section of the gas inlet 33 is substantially closed by the bundle 75 of the heat receiving tubes 31 constituting the inlet side pipe section 61. The entered combustion gas collides with the bundle 75 of the heat receiving pipes 31 constituting the inlet side pipe section 61 and exchanges heat with the heat receiving pipes 31 of the relevant part. A part of the combustion gas passes through the gap between the heat receiving pipes 31 and flows downward.

On the other hand, the remaining part of the combustion gas crosses the band of the heat receiving pipe 31 as shown by the arrow A and enters the first cavity 80 from the b section.
Of the combustion gas introduced into the case member 20 of the secondary heat exchanger 5, the combustion gas that has entered directly from the section a flows downward as shown in FIG. 15 and FIG. It enters into the first cavity 80 in the member 20, collides with the heat receiving pipe 31 constituting the outlet side pipe portion 65 in the bottom portion of the case member 20, and exchanges heat with the heat receiving pipe 31 in that portion.

Thus, the combustion gas that has entered the first cavity 80 flows toward the b section and the c section in the case member 22 as indicated by arrows A and B in FIGS. 15 and 16.
That is, the first cavity 80 of the a section communicates with the second cavity 83 below the inlet side pipe 61 as shown in FIGS. 15 and 16. Further, the first cavity 80 communicates with the c section through the opening 81. Accordingly, the first cavity 80 is open to the b section and the c section. On the other hand, as shown in the figure, there is a partition member 40 between the first cavity 80 in the a section and the d section in which the gas discharge port 35 is provided, and the first cavity 80 in the a section and the d section Between the two. That is, the partition member 40 partially partitions between the loop portion accommodation region 66 and the inlet / outlet pipe placement region 88 in the case member 20 and closes between the first cavity portion 80 of the a section and the d section. However, there is no partition between the first cavity 80 of the a section and the c section. Similarly, a shielding wall member 38 is also provided between the first cavity 80 in the a section and the d section in which the gas discharge port 35 is provided. It is closing the space.
Therefore, most of the combustion gas that has entered the first cavity 80 flows toward the b and c compartments in the case member 22 as indicated by arrows A and B in FIGS. It does not flow to the 35 side. However, since there is an interval of about 2 mm to 10 mm between the secondary bent portion 41 and the loop portion 55 of the partition plate 40, a part of the combustion gas flows into the d section and exchanges heat with the loop section of the d section. .

Then, the combustion gas that has entered the b section and the c section from the first cavity 80 flows along the inner wall of the case member 20, and generally flows along the heat receiving pipe 31 of the loop portion 55 of the pipe line member 21. That is, a gap is formed by the spacer 67 between the stages of the heat receiving pipes 31.
Further, the tips of the ribs 36 provided on the loop portion 55 and the peripheral wall portion 26 on the back side of the drawing come into contact with the loop portion 55, so that a gap 78 (FIG. 7) is secured between the peripheral wall portion 26 and the loop portion 55. ing. Further, there is a gap 79 between the peripheral wall 27 on the short side and the pipe member 21.
Therefore, the combustion gas that enters the section c from the first cavity 80, collides with the peripheral wall portion 26, and flows along the peripheral wall portion 26 flows between the stages of the loop portion 55 as indicated by an arrow C in FIGS. A gap 78 (FIG. 7) flows between the gap formed in FIG. 5 or between the peripheral wall portion 26 and the loop portion 55, and further flows along the peripheral wall portion 27 by colliding with the peripheral wall portion 27 that is a short side. That is, the combustion gas that has entered the c section from the first cavity 80 flows along the inner wall of the case member 20, during which heat exchange with the heat receiving pipe 31 occurs, enters the d section, and exits from the gas discharge port 35.

  On the other hand, the combustion gas that travels obliquely from the first cavity 80 and directly enters the d section passes through the gaps between the stages of the heat receiving pipes 31 as indicated by the arrow D in FIGS. It directly collides with the peripheral wall portion 28 on the long side, merges with the previous flow, and flows along the inner wall of the case member 20.

In the combustion apparatus 1 of the present embodiment, the route (arrow E) from the first cavity 80 or the second cavity 83 through the central portion of the loop portion 55 to the gas outlet 35 is indicated by the shielding wall member 38 and the spacer. Blocked by 67.
That is, the spacer 67 forms a predetermined gap between the steps of the heat receiving tubes 31, but as shown in FIG. 14, the portion where the spacer 67 is attached is located between the steps of the heat receiving tubes 31. The space is closed by the spacer 67 itself.
In the present embodiment, the spacer 67 is attached at a position between the gas inlet 33 and the gas outlet 35 as shown in FIGS. 2 and 3, and more specifically, at a position closest to the gas outlet 35. Thus, it is on a straight line 82 (FIGS. 2 and 10) connecting the opening portion 81 not sealed by the partition member 40 and the gas discharge port 35. In this embodiment, the straight line 82 is blocked by the spacer 67 itself. Therefore, a route (arrow E) from the hollow portions 80 and 83 through the central portion of the loop portion 55 to the gas discharge port 35 is blocked by the spacer 67 and passes through the central portion of the loop portion 55 from the hollow portions 80 and 83. Thus, the combustion gas is prevented from being discharged to the gas discharge port 35. This prevents the combustion gas from being discharged without contributing to heat exchange.

Thus, in the secondary heat exchanger 5 employ | adopted by this embodiment, there exists the big 1st cavity part 80 in the position right under the gas inlet 33, and the member which seals this directly does not exist. Therefore, the combustion gas introduced from the upstream combustion can body 3 enters the case member 20 without difficulty. Further, in the case member 20, the combustion gas flows along the inner wall of the case member 20, so that a large flow path resistance does not occur in the case member 20.
Further, the shortcut that flows directly from the gas inlet 33 to the gas outlet 35 is blocked by the partition member 40, the shielding wall member 38, and the spacer 67.
Therefore, the secondary heat exchanger 5 employed in the present embodiment has a small flow path resistance and a high heat exchange efficiency.
Furthermore, since the gas inlet 33 is located immediately below the combustion can body part 3, there is no need to insert a member for forming a flow path between the combustion can body part 3 and the secondary heat exchanger 5, and the overall height is low. .

  In the embodiment described above, the configuration including the elliptical loop portion 55 is exemplified, but the shape of the loop portion is arbitrary, and for example, includes a circular loop portion 90 as shown in FIG. Also good.

  In the previous embodiment, the inlet side pipe part 61 and the outlet side pipe part 65 both extend linearly, but have a curved portion like the inlet side pipe part 91 shown in FIG. There may be.

  In the previous embodiment, the protruding portion 36 that contacts a part of the pipe line member 21 is continuous in a rib shape, but may be an independent protrusion 39 as shown in FIG.

  Further, in the previous embodiment, the inlet side pipe part 61 and the outlet side pipe part 65 are arranged in the case 20, but for example, as shown in FIG. 61 and the outlet side pipe portion 65 may pass outside the case 20.

DESCRIPTION OF SYMBOLS 1 Combustion apparatus 2 Burner part 3 Combustion can body part 5 Secondary heat exchanger (communication path formation part)
6 Exhaust flow path forming part 20 Case member 21 Pipe line member 22 Case body 23 Top plate member (plate member)
24 Crevice 26, 27, 28 Peripheral wall part 31 Heat receiving pipe 33 Gas inlet 35 Gas outlet 36 Rib (protrusion part)
40 Partition member 50 Inlet side header 51 Outlet side header 55 Loop part 56 Inlet / outlet pipe part 61 Inlet side pipe part 65 Outlet side pipe part 66 Loop part accommodating area (main part accommodating area)
67 Spacer 75 Heat receiving tube bundle 76 Heat receiving tube bundle 78 Air gap 80 Air gap (first cavity)
83 Second cavity portion 88 I / O pipe arrangement area (cavity formation area)
90 Loop part 91 Entry side pipe part

Claims (3)

  Combustion can body part for generating combustion gas and allowing the combustion gas to pass downward in the vertical direction, an exhaust flow path forming part standing in parallel with the combustion can body part, and the combustion can body part and exhaust A communication passage forming portion for connecting the flow passage forming portion, the combustion can body portion and the exhaust flow passage forming portion are provided on the communication passage forming portion, and a pipe member for heat exchange in the communication passage forming portion. In the combustion apparatus with a built-in, the communication passage forming portion has a case member, and the case member has a gas introduction port communicating with the combustion can body portion, and a gas discharge port communicating with the exhaust flow passage forming portion, In the case member, there is a main part containing area where the main part of the pipe member is arranged, and there is a cavity forming area adjacent to a position substantially the same height as the main part containing area, and the gas introduction There is a cavity forming area just below the mouth, and the upper part of the main part containing area or the main part containing area The there is a gas outlet at the top near the combustion apparatus, characterized in that there is an exhaust channel openings at the top of the main portion accommodating region.   In the pipe member, a loop part as a main part, an inlet side pipe part for introducing a heat receiving body into the loop part, and an outlet side pipe part for discharging the heat receiving body from the loop part are arranged in series. 2. The combustion apparatus according to claim 1, wherein the loop portion is provided in a main portion accommodating region, and the inlet side tube portion and the outlet side tube portion are disposed in a cavity forming region.   The pipe member has a plurality of pipes arranged in parallel, the loop part is wound in a plurality of stages, and the inlet side pipe part and the outlet side pipe part are connected to the uppermost and lowermost stages of the plurality of stages. The inlet side pipe part and the outlet side pipe part are at different height positions, and the main part accommodating area and the cavity forming area are formed on the upper side of the inlet side pipe part and the outlet side pipe part located on the lower side. The combustion apparatus according to claim 1, wherein a partition member for partially partitioning between the two is provided.

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