JP2007315661A - Heat exchanger and water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger capable of providing high heat exchange efficiency by properly suppressing a problem wherein heat exchange efficiency is deteriorated due to generation of drain following latent heat recovery. <P>SOLUTION: In a heat exchanger B, a plurality of coil like tube parts 40A-40C are segmented into first and second heat exchange parts HT1, HT2 surrounding first and second areas 30a, 3b, and after combustion gas flows into a combustion gas passage 32 from the first area 30a through a plurality of gaps 31 of the first heat exchange part HT1, it passes through a plurality of gaps 31 of the second heat exchange part HT2 and flows into the second area 30b. Gaps 31 positioned in respective most inner circumference sides of the first and second heat exchange parts HT1, HT2 are formed wider than other gaps 31 positioned in outer peripheries thereof to suppress flow velocity reduction of the combustion gas passing through the plurality of gaps 31 of the first heat exchange part HT1, and to promote drain removal in the second heat exchange part HT2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat exchanger that uses a coiled water pipe to recover heat from combustion gas, and a hot water apparatus including the heat exchanger.

  The present applicant has previously proposed a heat exchanger described in Patent Document 1 as a specific example. This conventional one includes a can body and a water pipe having a plurality of coiled tube portions disposed in the can body. Each of the plurality of coiled tube portions is formed by connecting a plurality of loop portions in a spiral shape and forming gaps therebetween, but the diameters thereof are different, and the substantially concentric lap windings are formed. It is provided in the shape. In addition, the inner regions of the plurality of coiled tube parts are partitioned into first and second regions by a partition member, whereby the plurality of coiled tube parts are separated from each other by the first and second regions. It is divided into first and second heat exchanging portions surrounding the two regions. In addition, a combustion gas passage surrounded by the peripheral wall portion of the can body is formed on the outer periphery of the plurality of coiled tubular body portions.

  In the heat exchanger having such a configuration, when combustion gas is supplied to the first region, the combustion gas is a plurality of gaps of the first heat exchange unit among the plurality of coiled tube portions. To the combustion gas passage outside of it. Next, the combustion gas passes through the plurality of gaps of the second heat exchange section from the combustion gas passage and proceeds to the second region. In such a process, sensible heat can be recovered from the combustion gas by the first heat exchange unit, and latent heat can be recovered by the second heat exchange unit. Therefore, it is possible to increase the amount of heat recovered from the combustion gas and increase the heat exchange efficiency.

  However, in the prior art, there is still room for improvement in further improving the heat exchange efficiency as described below.

  That is, when latent heat recovery is performed in the second heat exchange section, water vapor in the combustion gas is condensed, and many drains (condensed water) are generated on the surface of the tubular body of the second heat exchange section. If such a drain remains attached to the tube surface and the tube surface is covered with the drain, direct contact between the tube and the combustion gas will be hindered, resulting in a decrease in heat exchange efficiency. . In order to avoid such a problem, it is desired to smoothly remove the drain from the surface of the tubular body of the second heat exchange section. However, in the prior art, the widths of the gaps of the plurality of coiled tube parts are aligned substantially uniformly, and the widths of the gaps are all reduced. With this, it is difficult to smoothly remove the drain from between the plurality of loop portions of each coiled tubular body portion, and it is difficult to appropriately avoid the above problems. In addition, the drain bridges between the plurality of loop portions and the water film is stretched, which may cause a problem that each gap is closed and the combustion gas flow path is narrowed to increase the exhaust resistance.

  Furthermore, in the prior art, like the second heat exchange unit, the first heat exchange unit also has a configuration in which a plurality of gaps are arranged substantially the same. On the other hand, the circumferential length of each of the plurality of gaps (when the loop portion is a hollow circle having a diameter d, the circumferential length of the gap between the loop portions is πd) is not constant. Is long. For this reason, the opening area of each clearance gap between the plurality of coiled tube parts gradually increases from the innermost coiled tube part to the outermost coiled tube part. However, according to such a configuration, as the combustion gas travels from the innermost circumferential gap of the first heat exchange portion toward the outermost circumferential gap, the flow velocity of the combustion gas becomes slower and the heat transfer coefficient becomes smaller. . In the prior art, there is still room for improvement in this respect.

JP-A-2005-321170

  The present invention has been conceived under such circumstances, and appropriately suppresses problems such as a decrease in heat exchange efficiency due to the occurrence of drain accompanying latent heat recovery, and high heat exchange efficiency. It is an object of the present invention to provide a heat exchanger capable of obtaining the above, and a hot water apparatus including the heat exchanger.

  In order to solve the above problems, the present invention takes the following technical means.

  The heat exchanger provided by the first aspect of the present invention includes a can body having a peripheral wall portion and a plurality of coil shapes each having a plurality of loop portions arranged via a plurality of gaps in the axial length direction of the can body. The plurality of coiled tube portions are arranged in the can body in a substantially concentric overlapping shape, and the plurality of gaps and the plurality of loop portions are arranged on the shaft. Combustion gas formed between the water pipe for heat exchange, which is also arranged in a direction intersecting the longitudinal direction, and the outermost peripheral part of the plurality of coiled tube parts and the peripheral wall part of the can A passage and an inner space region of the plurality of coiled tube portions are partitioned into first and second regions in the axial length direction, and the plurality of coiled tube portions are divided into the first and second regions. Partition members that divide the region into first and second heat exchanging portions that respectively surround the region When the combustion gas is supplied to the first region, the combustion gas then passes through the plurality of gaps of the first heat exchange portion from the inner peripheral portion toward the outer peripheral portion. In the process of proceeding to the combustion gas passage, sensible heat can be recovered from the combustion gas, and the plurality of gaps of the second heat exchange portion from the combustion gas passage to the portion closer to the inner periphery. A heat exchanger capable of recovering latent heat from the combustion gas in a process of passing through and proceeding to the second region, wherein the innermost of each of the first and second heat exchange units The plurality of gaps positioned closer to the periphery are larger in width in the axial length direction than the plurality of other gaps positioned on the outer periphery thereof, and the combustion gas passes through the plurality of gaps of the first heat exchange unit. While the flow velocity drop of the Drain of elimination that occurred with the latent heat recovery is characterized in that there is a possible promotion structure in the second heat exchange unit.

  According to such a configuration, the following effects can be obtained.

  About the 1st heat exchange part, since the width of a plurality of gaps located near the innermost circumference with the shortest perimeter length is made larger than the width of other gaps, a plurality of gaps located near the innermost circumference It is possible to prevent the opening area of the gap from becoming extremely small compared to a plurality of other gaps. On the other hand, the combustion gas travels from the innermost peripheral portion toward the outermost peripheral portion through the plurality of gaps of the first heat exchange portion. Therefore, the opening area of the gap does not increase extremely as the combustion gas advances, and it is avoided that the flow velocity greatly decreases. As a result, a problem that the heat recovery amount in the first heat exchanging portion is reduced due to the decrease in the flow velocity is appropriately suppressed.

  In addition, the width of the plurality of gaps located closer to the innermost circumference is also increased in the second heat exchange part, but the flow direction of the combustion gas with respect to the second heat exchange part is the first heat exchange part. Is the opposite. Therefore, in the second heat exchange section, the width of the gap located at the most downstream side in the traveling direction of the combustion gas is the largest. For this reason, in this 2nd heat exchange part, latent heat recovery is performed from combustion gas, and when a drain is generated in connection with this, this drain is made into the 2nd heat exchange part using the flow of combustion gas. Easier to eliminate inward. In particular, when the combustion gas travels through a plurality of gaps in the second heat exchanging portion, heat recovery is performed as the combustion gas travels toward the inner peripheral portion, and the temperature gradually decreases. As a result, the drain is most likely to be generated when passing through the gap closer to the innermost periphery. In the present invention, since the gap between the portions where the drain is most likely to be generated is increased, the discharge of a large amount of drain is further promoted. For this reason, it is possible to appropriately suppress a problem that the wide region of the tube surface of the second heat exchange part remains covered with the drain and the heat exchange efficiency is lowered. Further, it is possible to eliminate a phenomenon in which the drain is bridged to the innermost clearance and the exhaust resistance is increased. In the second heat exchanging portion, unlike the first heat exchanging portion, there is little problem that the heat transfer coefficient is greatly reduced due to a significant decrease in the flow velocity of the combustion gas, and the flow velocity of the combustion gas is reduced. Higher heat exchange efficiency can be achieved by properly removing the drain from the tube surface than by speeding up.

  The heat exchanger provided by the second aspect of the present invention includes a can body having a peripheral wall portion and a plurality of coil shapes each having a plurality of loop portions arranged via a plurality of gaps in the axial length direction of the can body. The plurality of coiled tube portions are arranged in the can body in a substantially concentric overlapping shape, and the plurality of gaps and the plurality of loop portions are arranged on the shaft. Combustion gas formed between the water pipe for heat exchange, which is also arranged in a direction intersecting the longitudinal direction, and the outermost peripheral part of the plurality of coiled tube parts and the peripheral wall part of the can A passage and an inner space region of the plurality of coiled tube portions are partitioned into first and second regions in the axial length direction, and the plurality of coiled tube portions are divided into the first and second regions. Partition members that divide the region into first and second heat exchanging portions that respectively surround the region When the combustion gas is supplied to the first region, the combustion gas then passes through the plurality of gaps of the first heat exchange portion from the inner peripheral portion toward the outer peripheral portion. In the process of proceeding to the combustion gas passage, sensible heat can be recovered from the combustion gas, and the plurality of gaps of the second heat exchange portion from the combustion gas passage to the portion closer to the inner periphery. A heat exchanger capable of recovering latent heat from the combustion gas in the process of passing toward the second region and being located closer to the innermost periphery of the second heat exchange unit The plurality of gaps have a larger width in the axial length direction than other gaps located on the outer periphery of the gaps, and it is possible to promote the removal of drains generated due to the recovery of latent heat in the second heat exchange unit. That it is configured It is a symptom.

  According to such a configuration, as described for the second heat exchanging part of the heat exchanger provided by the first aspect of the present invention, the drain generated by the latent heat recovery is set to the second heat exchanging part. It can be smoothly removed from the tube surface of the exchange part, and the heat exchange efficiency can be increased.

  In a preferred embodiment of the present invention, the plurality of coiled tube parts include three or more coiled tube parts, and among these three or more coiled tube parts, a coil closer to the innermost circumference. The width in the axial length direction of the plurality of gaps is configured so as to gradually decrease from the cylindrical tube portion toward the coiled tubular portion near the outermost periphery.

  According to such a configuration, it is possible to more appropriately prevent the speed at which the combustion gas passes through the plurality of gaps of the first heat exchanging portion from significantly decreasing in the middle. In addition, in the second heat exchange section, the width of other gaps can be increased in addition to the gap near the innermost periphery, and therefore, drain elimination is further promoted.

  In a preferred embodiment of the present invention, among the first and second heat exchanging portions, at least the plurality of gaps of the first heat exchanging portion have their respective peripheral lengths and widths in the axial length direction. Are formed to be substantially the same.

  According to such a configuration, since the opening area is almost the same in any gap from the gap near the innermost circumference to the gap near the outermost circumference of the first heat exchange part, the flow velocity of the combustion gas Is fixed. As a result, it is optimal for increasing the heat transfer coefficient.

  In a preferred embodiment of the present invention, the plurality of coiled tube parts include a first coiled tube part located on the innermost periphery and an outer periphery of the first coiled tube part. There are a plurality of second coiled tube parts positioned, and the first coiled tube part has a larger diameter than the plurality of second coiled tube parts, and the plurality of second coiled tube parts. In the coiled tube portion, the dimensions and tube diameters of the plurality of gaps in the axial length direction are substantially the same.

  According to such a configuration, the tube diameter of the innermost first coil-shaped tube portion is increased, and the amount of hot water flowing through the inside increases. On the other hand, the first coiled tube portion is a portion directly surrounding the first region to which the combustion gas is first supplied, and is most susceptible to heat. Therefore, it is suitable for increasing the amount of heat recovered from the combustion gas, and boiling of hot water is less likely to occur. In addition, since the plurality of second coiled tube portions are substantially the same in size and tube diameter, the manufacturing of the second coiled tube portions is different from the case where the dimensions are different. It becomes easy.

  The hot water device provided by the third aspect of the present invention supplies the combustion gas to the heat exchanger provided by the first or second aspect of the present invention and the first region of the heat exchanger. And a combustor.

  According to such a configuration, the same effect as described for the heat exchanger provided by the first or second aspect of the present invention can be obtained.

  Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention with reference to the accompanying drawings.

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

  1 to 4 show a hot water supply apparatus as a specific example of a hot water apparatus to which the present invention is applied and a configuration related thereto. As clearly shown in FIG. 1, the hot water supply apparatus A of this embodiment includes a combustor 1, a heat exchanger B, a bottom casing 80, and an exhaust duct 81.

  The combustor 1 is of a reverse combustion type in which fuel oil such as kerosene or light oil is sprayed downward by a spray nozzle 14 and burned. The sprayed fuel sprayed from the spray nozzle 14 is mixed with combustion air in the burner cylinder 11 and then discharged downward to burn. The combustor 1 is covered and supported by a can body 10 mounted on the heat exchanger B, and fuel is supplied from the outside of the can body 10 via a pipe 12. . A blower fan 13 for supplying combustion air to the combustor 1 and a motor M that drives the blower fan 13 are provided on the upper portion of the can body 10.

  The heat exchanger B includes a can body 2, a plurality of (in this embodiment, a total of four) water pipes 4 </ b> A to 4 </ b> D, a pair of headers 49 a and 49 b for incoming and outgoing hot water, and a partition member 6.

  The can body 2 has a substantially cylindrical peripheral wall portion 20 and a pair of cover bodies 21A and 21B attached to the upper and lower portions of the peripheral wall portion 20, and is placed on the bottom casing 80. . The cover body 21A forms an opening 22A into which the lower part of the burner cylinder 11 enters. The cover body 21 </ b> B forms an opening 22 </ b> B for guiding the combustion gas after heat recovery by the plurality of water tubes 4 </ b> A to 4 </ b> D into the bottom casing 80. The can body 2 is made of, for example, stainless steel, and is not easily corroded due to a drain generated when latent heat is recovered from combustion gas using the water tubes 4A to 4D. In general, the drain generated with the recovery of latent heat from the combustion gas is strongly acidic, such as PH3, which has absorbed sulfur oxides, nitrogen oxides, and the like in the combustion gases. For this reason, the can 2 is made of a material excellent in acid resistance. This is the same for the plurality of water tubes 4A to 4D, and the material thereof is, for example, stainless steel.

  The plurality of water tubes 4 </ b> A to 4 </ b> D include coiled tube portions 40 </ b> A to 40 </ b> D disposed in the can 2. The coiled tube portions 40A to 40D are all spiral and have a configuration in which a series of hollow circular loop portions 40a connected in series are stacked in a plurality of stages in the vertical direction. However, the coiled tube portions 40A to 40D have different winding diameters and are arranged in a substantially concentric overlapping winding shape. In the present embodiment, the pipe diameters of the plurality of water pipes 4A to 4D are the same, but the pipe diameters may be different as in the embodiment described later. A space 3 is formed inward of the plurality of coiled tube portions 40A to 40D. A combustion gas passage 32 is formed between the outermost coiled tube portion 40 </ b> D and the peripheral wall portion 20 of the can body 2.

  Between each of the loop portions 40a adjacent to each other in the vertical direction of the plurality of coiled tube portions 40A to 40D, a combustion gas passage gap 31 that connects the space portion 3 and the combustion gas passage 32 is formed. As shown in FIG. 3, each gap 31 is formed by providing a plurality of deformed portions 42 flattened in each loop portion 40a at appropriate intervals. More specifically, as shown in FIGS. 4 (a) and 4 (b), each loop portion 40a is formed using a round pipe having a pipe diameter D1. A flat deformed portion 42 is provided which is pressed so that the width s1 is larger than the tube diameter D1, and the horizontal width s2 is smaller than the tube diameter D1. Since the deforming portions 42 are in contact with each other, the other portions between the loop portions 40 are gaps 31. Therefore, the vertical width of each gap 31 can be changed as appropriate by changing the width s1 of the deformed portion. However, in the present invention, as a means for setting each gap 31 to a desired size, for example, a means of interposing a spacer between adjacent loop portions 40a can be adopted.

As shown well in FIG. 2, the vertical width of the plurality of gaps 31 is the largest dimension in the innermost coiled tubular part 40A and is directed toward the outermost coiled tubular part 40D. It gradually gets smaller as you move forward. When the vertical widths of the gaps 31 of the plurality of coiled tube portions 40A to 40D are w1 to w4 and the diameters of the loop portions 40a are d1 to d4, in this embodiment, the coiled tube Except for a part of the upper and lower ends of the body parts 40A to 40D, they are configured so as to substantially satisfy the relationship of the following formulas 1 ′ and 1 over substantially the whole thereof.
π · d1 · w1 = π · d2 · w2 = π · d3 · w3 = π · d4 · w4 (Formula 1 ′)
Therefore, d1 · w1 = d2 · w2 = d3 · w3 = d4 · w4 (Formula 1)

  In FIG. 1, the pair of headers 49 a and 49 b are connected to the lower ends and the upper ends of the plurality of coiled tube portions 40 </ b> A to 40 </ b> D via joint tubes 41. A water supply pipe (not shown) is connected to the header 49a, and water such as tap water supplied from the water supply pipe is supplied into the coiled tube portions 40A to 40D. A hot water pipe (not shown) is connected to the header 49b, and hot water heated by passing through the coiled tube portions 40A to 40D is sent to a desired hot water supply destination through the hot water pipe.

  The partition member 6 is made of, for example, stainless steel, and as shown in FIG. 2, the partition member 6 is formed in a bowl shape or a concave dish shape in which the upper surface portion is recessed, and the upper surface is covered with a heat insulating material 68 such as ceramic fiber. It has a broken main body 60 and a flange 61 connected to the outer periphery of the upper portion of the main body 60. The partition member 6 is attached to the innermost coiled tubular body portion 40 </ b> A using the flange portion 61, and closes the middle portion in the vertical direction of the space portion 3. As a result, the space 3 is partitioned into the first and second regions 30a and 30b. Further, the plurality of coiled tube portions 40A to 40D are divided into first and second heat exchange portions HT1 and HT2 that surround the first and second regions 30a and 30b, respectively. If the partition member 6 has a bowl shape or a concave dish shape as described above, there is an advantage that the volume of the first region 30a that also serves as a combustion chamber can be increased.

  Of the bottom of the can body 2, the portion between the lower portion of the peripheral wall portion 20 and the annular wall 221 of the cover body 21 </ b> B receives a drain dripping from the water pipes 4 </ b> A to 4 </ b> D along with the recovery of latent heat from the combustion gas. The drain receiving portion 26 is provided. The drain receiving portion 26 is provided with a drain outlet 26a, and as shown in FIG. 1, the drain is discharged to the outside through a pipe 26b connected to the outlet 26a. Has been.

  The bottom casing 80 has a substantially rectangular parallelepiped box shape with a hollow inside, and the heat exchanger B and the exhaust duct 81 are placed on the bottom casing 80 so as to be aligned. The combustion gas that has passed through the can 2 of the heat exchanger B flows downward into the bottom casing 80 from the opening 80a, and then upwards from the other opening 80b to the bottom opening of the exhaust duct 81. Is going to progress. The combustion gas flowing into the exhaust duct 81 is then discharged to the outside as exhaust gas from the exhaust port 81a.

  Next, the operation of the hot water supply apparatus A will be described.

  First, when the combustor 1 is driven, combustion gas is supplied into the first region 30a of the space 3, and this combustion gas travels downward and collides with the upper surface portion of the partition member 6, and below it. Is prevented from proceeding to. Then, the combustion gas passes through the plurality of gaps 31 of the first heat exchanging part HT1 and enters the combustion gas passage 32 while circulating along a fixed path in the first region 30a as shown by the arrow in the drawing. Inflow. In this process, the first heat exchange unit HT1 performs heat recovery from the combustion gas. The combustion gas travels from the gap 31 of the innermost coiled tube portion 40A toward the gap 31 of the outermost coiled tube portion 40D. The widths w1 to w4 in the direction are increased toward the inner periphery, and their opening areas are substantially the same. Therefore, the flow velocity of the combustion gas when passing through the plurality of gaps 31 is substantially constant, and no significant decrease in the flow velocity occurs. As a result, it is possible to prevent the heat exchange efficiency of the first heat exchange part HT1 from greatly decreasing due to a reduction in the flow velocity of the combustion gas, and to reduce the size of the first heat exchange part HT1 while reducing the size of the first heat exchange part HT1. It becomes possible to appropriately recover sensible heat from the gas.

  Next, after the combustion gas travels downward in the combustion gas passage 32, it passes through the plurality of gaps 31 of the second heat exchange part HT2 and flows into the second region 30b. In this process, the second heat exchange unit HT2 recovers latent heat from the combustion gas. Along with this latent heat recovery, many drains are generated on the surface of the tubular body of the second heat exchange section HT2. Unlike the case of the first heat exchanging part HT1 described above, the combustion gas flows from the outermost coiled tubular part 40D to the innermost circumference with respect to the plurality of gaps 31 of the second heat exchanging part HT2. It progresses toward the coiled tubular part 40A. On the other hand, the widths w1 to w4 of the plurality of gaps 31 increase toward the inner periphery, and gradually increase as the combustion gas advances. For this reason, the combustion gas causes the drain generated on the surface of the tube to flow in the direction where the width of the gap is larger, and the coiled tube portion 40A formed at the innermost circumference and having the largest width w1. Thus, an effect of flowing the drain down to the second region 30b can be obtained. In particular, since the temperature of the combustion gas gradually decreases from the outer circumferential gap 31 to the inner circumferential gap 31, the amount of generated drain is larger than the outer circumferential area of the second heat exchange unit HT <b> 2. However, it increases as it moves toward the inner periphery. On the other hand, since the width of the plurality of gaps 31 increases as the portion where the amount of generated drain increases as described above, an effect of further promoting the removal of the generated drain is obtained. For this reason, a problem that a large area of the surface of the tubular body of the second heat exchange part HT2 is covered with many drains and heat transfer from the combustion gas is prevented is appropriately suppressed. As a result, also in the second heat exchange section HT2, the heat exchange efficiency can be increased, and a large amount of latent heat can be recovered while reducing the size. Further, if the width of the gap 31 increases as the combustion gas advances, the drain resistance bridges in a water film shape at each of the gaps 31 and the exhaust resistance increases appropriately. . The drain dropped downward from the second heat exchanging portion HT2 is received by the drain receiving portion 26 and then discharged to the outside through the discharge port 26a and the pipe 62b.

  The plurality of gaps 31 of the second heat exchanging part HT2 are also substantially equal in opening area from the outer peripheral part to the inner peripheral part, like the plural gaps 31 of the first heat exchanging part HT1. It has been. Therefore, the flow rate of the combustion gas when passing through the plurality of gaps 31 of the second heat exchange part HT2 is also substantially constant, and there is no significant decrease in the flow rate. In the second heat exchanging portion HT2, unlike the present embodiment, even if a phenomenon occurs in which the flow velocity of the combustion gas slightly decelerates due to the increase in the width of the gap 31 near the inner periphery. Increasing the heat transfer coefficient by eliminating the drain is effective in improving the heat exchange efficiency.

  FIG. 5 shows another embodiment of the present invention. In these drawings, elements that are the same as or similar to those in the above embodiment are given the same reference numerals as in the above embodiment.

  In the embodiment shown in FIG. 5, the water pipe 4A ′ and the other water pipes 4B to 4D have different pipe diameters, and the coiled tubular body portion 40A ′ located on the innermost circumference has other coils. Compared to the tubular portions 40B to 40D, the tube diameter is large, and the vertical width w5 of each gap 31 is also increased. The tube diameters of the other coiled tube portions 40B to 40D and the width w6 of each gap 31 are substantially the same. The coiled tube portions 40A ′ and 40B to 40D are divided into first and second heat exchange portions HT1 and HT2 as in the above embodiment.

  In the present embodiment, the widths w6 of the gaps 31 of the plurality of coiled tube portions 40B to 40D are the same, and the opening areas of these portions are not configured to be substantially the same. However, since the gap 31 of the innermost coiled tubular part 40A ′ is wider than the gaps 31 of the other coiled tubular parts 40B to 40D, the combustion gas passes through the first heat exchange part HT1. It is appropriately suppressed that the speed of passing from the inside toward the outside greatly decreases. Further, the drain generated in the second heat exchanging portion HT2 is smoothly removed from each gap 31 of the innermost coiled tube portion 40A 'toward the second region 30b. In particular, it is possible to obtain an effect that the drain is smoothly eliminated at a position where the most drain can be generated at the most downstream in the traveling direction of the combustion gas. As will be understood from the present embodiment, in the present invention, the width of each gap of the plurality of coiled tube portions is not reduced sequentially as it proceeds from the innermost circumference to the outermost circumference, and the innermost circumference is increased. Only the gap can be made larger than the other gaps.

  Moreover, according to the said embodiment, the pipe diameter of coil-shaped pipe part 40A 'is large, and there are many internal hot water flow rates. On the other hand, the coiled tube portion 40A ′ directly surrounds the first region 30a having the highest combustion gas temperature in the can 2, so that the amount of heat recovered by hot water can be increased. . It is also suitable for preventing boiling of hot water. On the other hand, since the other pipe-shaped tube portions 40B to 40D have the same tube diameter and the same width of the gap w6, the manufacturing is facilitated compared to the case where these values are different. Cost reduction can be achieved.

  The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the heat exchanger and the hot water apparatus according to the present invention can be varied in design in various ways.

  In the heat exchanger of the present invention, preferably, the innermost clearance of each of the first and second heat exchange units is configured to be larger than the other clearances. However, only the second heat exchanging unit is configured as described above, and the first heat exchanging unit may be configured in the same manner as in the related art. Also according to such an aspect, it is possible to considerably increase the heat exchange efficiency as compared with the prior art, and such an aspect is also included in the technical scope of the invention.

  There may be a plurality of coiled tube portions, and the specific number thereof can be arbitrarily selected. The loop part of each coil-shaped tube part is not limited to a hollow circular shape, and may be, for example, a hollow rectangular shape. The can body can also be formed in, for example, a rectangular tube shape by corresponding to the shape of each coiled tube portion. As the combustor, in addition to the oil combustor, a gas combustor or the like can be used. The combustion method of the combustor may be a forward combustion method in which the combustion gas is advanced upward, a method in which the combustion gas is advanced in the lateral direction, for example, instead of the reverse combustion method in which the combustion gas is advanced downward in the combustor.

  The hot water device as used in the present invention means a device having a function of generating hot water, and is used for various types of hot water supply devices for general hot water supply, bath hot water supply, heating, snow melting, and the like, and hot water supply. Includes a device for producing hot water.

It is a schematic sectional drawing which shows an example of the hot water supply apparatus with which this invention was applied. It is principal part sectional drawing of the hot-water supply apparatus shown in FIG. FIG. 3 is a schematic sectional view taken along line III-III in FIG. 2. (a) is side explanatory drawing of the coil-shaped pipe part of the water pipe of the hot water supply apparatus shown by FIGS. 1-3, (b) is IV-IV sectional drawing of (a). It is principal part sectional drawing which shows the other example of the hot water supply apparatus with which this invention was applied.

Explanation of symbols

A Hot water supply device (hot water device)
B heat exchanger HT1 1st heat exchange part HT2 2nd heat exchange part 1 combustor 2 can body (of heat exchanger)
3 space part (space area inside coiled tube part)
4A to 4D Water pipe 6 Partition member 30a First region 30b Second region 31 Gap 32 Combustion gas passage 40a Loop part 40A to 40D Coiled tube part

Claims (6)

A can having a peripheral wall,
The can body includes a plurality of coiled tube portions each having a plurality of loop portions arranged in the axial length direction through a plurality of gaps, and the plurality of coiled tube portions are substantially concentrically wound. The plurality of gaps and the plurality of loop portions are arranged in the direction intersecting the axial length direction by being arranged in the can body, and a water tube for heat exchange,
A combustion gas passage formed between the outermost peripheral part of the plurality of coiled tube parts and the peripheral wall part of the can;
An inner space region of the plurality of coiled tube portions is partitioned into first and second regions in the axial length direction, and the plurality of coiled tube portions are divided into the first and second regions, respectively. A partition member that divides the enclosed first and second heat exchange sections,
When the combustion gas is supplied to the first region, the combustion gas then passes through the plurality of gaps of the first heat exchange portion from the inner peripheral portion toward the outer peripheral portion and enters the combustion gas passage. In the process of progress, sensible heat can be recovered from the combustion gas, and the plurality of gaps of the second heat exchange section are passed from the combustion gas passage toward the inner peripheral portion through the plurality of gaps of the second heat exchange portion. A heat exchanger capable of recovering latent heat from the combustion gas in the process of proceeding to the region of 2,
The plurality of gaps positioned closer to the innermost circumference of each of the first and second heat exchange parts have a larger width in the axial length direction than the plurality of other gaps positioned on the outer periphery thereof, While the flow velocity reduction of the combustion gas passing through the plurality of gaps of the first heat exchange part is suppressed, the second heat exchange part is configured to be able to promote the elimination of the drain generated due to the latent heat recovery. A heat exchanger, characterized in that A can having a peripheral wall,
The can body includes a plurality of coiled tube portions each having a plurality of loop portions arranged in the axial length direction through a plurality of gaps, and the plurality of coiled tube portions are substantially concentrically wound. The plurality of gaps and the plurality of loop portions are arranged in the direction intersecting the axial length direction by being arranged in the can body, and a water tube for heat exchange,
A combustion gas passage formed between the outermost peripheral part of the plurality of coiled tube parts and the peripheral wall part of the can;
An inner space region of the plurality of coiled tube portions is partitioned into first and second regions in the axial length direction, and the plurality of coiled tube portions are divided into the first and second regions, respectively. A partition member that divides the enclosed first and second heat exchange sections,
When the combustion gas is supplied to the first region, the combustion gas then passes through the plurality of gaps of the first heat exchange portion from the inner peripheral portion toward the outer peripheral portion and enters the combustion gas passage. In the process of progress, sensible heat can be recovered from the combustion gas, and the plurality of gaps of the second heat exchange section are passed from the combustion gas passage toward the inner peripheral portion through the plurality of gaps of the second heat exchange portion. A heat exchanger capable of recovering latent heat from the combustion gas in the process of proceeding to the region of 2,
The plurality of gaps positioned closer to the innermost periphery of the second heat exchange section have a larger width in the axial length direction than the plurality of other gaps located on the outer periphery thereof, and the second heat exchange The heat exchanger is characterized in that it can promote the removal of the drain generated by the latent heat recovery in the section. As the plurality of coiled tube parts, there are three or more coiled tube parts,
Among these three or more coiled tube portions, the width in the axial length direction of the plurality of gaps sequentially increases from the coiled tube portion closer to the innermost periphery to the coiled tube portion closer to the outermost periphery. The heat exchanger according to claim 1 or 2, wherein the heat exchanger is configured to be small.   Among the first and second heat exchanging portions, at least the plurality of gaps of the first heat exchanging portion are formed such that the product of their respective peripheral lengths and the width in the axial length direction are substantially the same. The heat exchanger according to any one of claims 1 to 3, wherein   As the plurality of coiled tube parts, a first coiled tube part located on the innermost periphery and a plurality of second coiled tubes located on the outer periphery of the first coiled tube part. The first coiled tube body portion has a larger diameter than the plurality of second coiled tube body portions, and the plurality of second coiled tube body portions include The heat exchanger according to claim 1 or 2, wherein each of a plurality of gaps in the axial length direction and the pipe diameter are substantially the same.   A hot water apparatus comprising: the heat exchanger according to any one of claims 1 to 5; and a combustor that supplies combustion gas to the first region of the heat exchanger.

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