JP2007155221A - Combustion heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently heat an object to be heated, and to prevent incomplete combustion due to leakage of premixed gas, in a combustion heater provided with a combustion chamber 15 of a center part, an air supply passage 16 supplying the premixed gas to the combustion chamber, and an exhaust passage 17 passing combustion gas generated by combustion of the premixed gas in the combustion chamber in a body 2 with one side face covered by a heating plate 12 for heating the object to be heated, and another side face covered by a heat insulating plate 13. <P>SOLUTION: A partition plate 14 is provided between the heating plate 12 and the heat insulating plate 13, the exhaust passage 17 is formed between the heating plate 12 and the partition plate 14, and the air supply passage 16 is formed between the heat insulating plate 13 and the partition plate 14. The combustion chamber 15 is divided into a heat insulating plate side and a heating plate side by the partition plate 14, and a communication hole 18 with a smaller area than a cross-sectional area of the combustion chamber 15, communicating the two portions is formed in the partition plate 14. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a combustion heater using a micro combustor (small combustor) technique.

  Conventionally, a combustion heater using a Swiss roll type micro combustor is known (see, for example, Patent Document 1). This combustion heater has a combustion chamber in the center and a combustion chamber in a container in which one side surface facing is covered with a heating plate for heating an object to be heated and the other side surface is covered with a heat insulating plate. A double spiral channel is provided at the center, and one spiral channel is used as an air supply channel for supplying a premixed gas to the combustion chamber, and the other spiral channel is a premixed gas in the combustion chamber. This is an exhaust passage through which combustion gas generated by the combustion of the gas flows. The premixed gas is preheated by exchanging heat with the combustion gas via a spiral guide wall that partitions the air supply passage and the exhaust passage, and combustion continues even in a small combustion chamber. Then, the heating plate is heated by the heat of the combustion gas, and the object to be heated is heated by heat transfer or radiant heat from the heating plate.

  This combustion heater can be used as an alternative to an electric heater. Also, if this combustion heater is used instead of a gas stove burner, it will be safe because there will be no open flame, and the heating section will be flat and easy to clean, which is the same effect as the recently popular IH stove. Is obtained.

However, the conventional combustion heater has the following problems. In other words, this combustion heater has a structure in which one side of the air supply channel and the exhaust channel are both closed by the heating plate, and the other side of both channels is closed by the heat insulating plate. The combustion gas flowing in the passage touches not only the heating plate but also the heat insulating plate, and the heat insulating plate is directly heated by the combustion gas. As a result, it becomes difficult to completely prevent the heat release of the combustion gas through the heat insulating plate. Furthermore, in addition to the combustion gas flowing in the exhaust passage in addition to the combustion gas flowing to the heating plate, the premixed gas flowing in the supply passage is also touched so that the heating plate becomes an intermediate temperature between the combustion gas and the premixed gas, and the combustion gas passes through the heat insulating plate. Combined with the heat dissipation loss, the heating efficiency of the object to be heated becomes worse. In addition, the air supply channel and the exhaust channel are partitioned by the spiral guide wall as described above, but it is difficult to airtightly join the side edge of the guide wall to the heating plate and the heat insulating plate over the entire length thereof. In addition, the premixed gas may leak from the supply passage to the exhaust passage before the combustion chamber, resulting in incomplete combustion.
Japanese Patent Laid-Open No. 2004-20083

  In view of the above points, the present invention has improved the above-described conventional combustion heater so that the object to be heated can be efficiently heated, and the occurrence of incomplete combustion due to leakage of the premixed gas can be prevented. The problem is to provide a high quality combustion heater.

  In order to solve the above-described problems, the present invention is directed to the combustion of a central portion in a container in which one side surface facing is covered with a heating plate for heating an object to be heated and the other side surface is covered with a heat insulating plate. Chamber, an air supply passage for supplying the premixed gas to the combustion chamber, and an exhaust passage through which the combustion gas generated by the combustion of the premixed gas in the combustion chamber flows are provided, and the heat of the combustion gas flowing in the exhaust passage In the combustion heater in which the premixed gas flowing through the air supply passage is preheated and the heating plate is heated, the combustion heater includes a partition plate provided between the heating plate and the heat insulating plate, An exhaust passage is provided between the partition plate and an air supply passage is provided between the heat insulating plate and the partition plate, and heat exchange between the combustion gas and the premixed gas is performed via the partition plate. It is characterized by the fact that

  According to the present invention, the premixed gas is preheated by heat exchange with the combustion gas via the partition plate, and combustion continues in a small combustion chamber as in the conventional combustion heater. In the present invention, since the combustion gas flows through the exhaust passage between the heating plate and the partition plate without touching the heat insulating plate, the heat insulating plate is not heated by the combustion gas, and the combustion gas passes through the heat insulating plate. Can be easily prevented. Furthermore, since the premixed gas flows through the air supply passage between the heat insulating plate and the partition plate without touching the heating plate, the heating plate is heated to a high temperature without taking heat away from the premixed gas, In combination with the ability to prevent the loss of heat dissipation of the combustion gas, the object to be heated can be heated with high efficiency.

  Further, in the present invention, since the air supply flow path and the exhaust flow path are partitioned by the partition plate, the premixed gas does not leak from the air supply flow path to the exhaust flow path. Complete combustion can be reliably prevented.

  In the present invention, the combustion chamber is divided into two parts, a part on the heat insulating plate side and a part on the heating plate side, by the partition plate, and is smaller than the cross-sectional area of the combustion chamber that communicates the two parts with the partition plate. It is desirable that a communication hole having an area is formed. According to this, the combustion chamber is throttled in the middle, and the premixed gas flowing from the air supply passage into the portion on the heat insulation plate side of the combustion chamber is short-circuited to the exhaust passage through the portion on the heating plate side of the combustion chamber. Flow is prevented. Therefore, the residence time of the premixed gas in the combustion chamber is ensured, and combustion is stabilized.

  Further, it is desirable that the air supply passage and the exhaust passage are each formed in a spiral shape with the combustion chamber as the center. According to this, a swirling flow of the premixed gas is generated in the combustion chamber, and the residence time of the premixed gas in the combustion chamber is ensured and the mixing is promoted to further stabilize the combustion. Further, the length of the exhaust passage is increased, the contact time of the combustion gas with the heating plate is increased, and the heating plate is efficiently heated.

  By the way, in the above-mentioned conventional combustion heater, the direction of the vortex in the air supply passage and the direction of the vortex in the exhaust passage are the same. That is, when the supply air flow path is a spiral swirling clockwise, for example, from the outside toward the central combustion chamber, the exhaust flow path is also a swirl swirling clockwise from the outside, toward the central combustion chamber. This means that the exhaust flow path becomes a spiral swirling counterclockwise from the central combustion chamber. Therefore, the swirl direction of the combustion gas flowing out from the combustion chamber to the exhaust flow path is opposite to the swirl direction of the premixed gas flowing into the combustion chamber from the supply air flow path. As a result, the passage resistance increases, and it is necessary to increase the capacity of the air supply device that supplies the premixed gas to the air supply flow path. On the other hand, if the swirl direction of the supply air flow path and the swirl direction of the exhaust flow path are opposite to each other, the swirling direction of the premixed gas flowing into the combustion chamber from the supply air flow path and the exhaust flow path from the combustion chamber The swirling direction of the combustion gas flowing out into the air flow direction is the same, the passage resistance is reduced, and the air supply device that supplies the premixed gas to the air supply flow path has a relatively small capacity, so that the cost can be reduced. Is advantageous.

  Here, the inflow portion of the premixed gas from the supply passage to the combustion chamber may be formed so that the width of the inflow portion is equal to or less than the extinguishing distance to prevent backfire from the combustion chamber to the intake passage. is necessary. Therefore, when the supply flow rate of the premixed gas is increased, the flow rate of the premixed gas in the inflow portion having a limited area is increased, and a flame blowing phenomenon is likely to occur. In this case, if a plurality of inflow portions of the premixed gas from the air supply passage formed in a spiral shape to the combustion chamber are provided, the flow area of the premixed gas in each inflow portion decreases as the total area of the inflow portion increases. Thus, the occurrence of a flame blowing phenomenon is prevented. Furthermore, the flow of the premixed gas in the combustion chamber becomes uniform, and combustion is further stabilized.

  The shapes of the air supply channel and the exhaust channel are not limited to the spiral shape. For example, the air supply channel may be formed radially with the combustion chamber as the center. If a plurality of inflow portions of the premixed gas to the combustion chamber are provided at the radially inner ends of these radial air supply passages, the flow velocity of the premixed gas in each inflow portion decreases, and the flame Is prevented from occurring, and at the center of the combustion chamber, premixed gas from the respective inflow portions collide with each other to create a stagnation point where the flow velocity becomes almost zero, and ignition is easy. Furthermore, the flow of the premixed gas in the combustion chamber becomes uniform, and the combustion is stabilized.

  In addition, when the air supply flow path and the exhaust flow path are respectively formed in a spiral shape or a radial shape centering on the combustion chamber, the air supply flow path and the exhaust flow path can be sufficiently preheated by the combustion gas. It is conceivable to narrow the flow path width and increase the total flow path length of the air supply flow path and the exhaust flow path. However, this increases the passage resistance and makes it necessary to increase the capacity of the air supply device. On the other hand, on the side surface of the partition plate facing at least one of the heating plate and the heat insulating plate, the air supply channel or the exhaust channel formed between the one plate and the partition plate If the fin portion is provided so as to be positioned within the width so as to leave a gap between the one plate, the heating efficiency of the premixed gas by the combustion gas is enhanced by the fin portion. Therefore, the premixed gas can be sufficiently preheated by the combustion gas without reducing the width of the air supply flow path or the exhaust flow path so much, and the air supply apparatus can be of a relatively small capacity.

  In addition, in order to efficiently heat the heating plate with the combustion gas, it is conceivable to narrow the width of the spiral or radial exhaust flow path, but this increases the passage resistance and increases the capacity of the air supply device. It needs to be high. On the other hand, on the inner surface facing the partition plate of the heating plate, if it is located within the flow channel width of the exhaust channel and a fin portion protrudes so as to leave a gap with the partition plate The heating efficiency of the heating plate by the combustion gas is enhanced by the fin portion. Therefore, the heating plate can be efficiently heated by the combustion gas without reducing the width of the exhaust passage so much, and the air supply device can have a relatively small capacity.

  The premixed gas is ignited by a spark plug. If the ignition plug is inserted into the combustion chamber from the heat insulating plate side, the ignition plug cord can be prevented from being damaged by heat.

  Referring to FIG. 1, reference numeral 1 denotes a combustion heater used as a heat source for a gas stove. The combustion heater 1 includes a disk-shaped body 2, an air supply joint 3 on one side around the body 2, and an exhaust joint 4 on the other side around the body 2. The air supply device 5 is connected. The air supply device 5 includes a blower 6 and a venturi mixer 8 interposed in a passage 7 that guides air from the blower 6 to the air supply joint 3. The venturi mixer 8 includes an electromagnetic valve 9 and a zero governor 10. Combustion gas is supplied through the interposed gas passage 11. The zero governor 11 adjusts the secondary pressure to atmospheric pressure. The fuel gas is sucked into the venturi mixer 8 at a flow rate proportional to the air flow rate, and a premixed gas having an excess air ratio of about 1.1 is generated. .

  The body 2 of the combustion heater 1 is covered with a heating plate 12 made of a heat-resistant alloy for heating an object to be heated such as a cooking vessel, as shown in FIG. The other side surface (lower surface) is covered with a heat insulating plate 13 made of a heat-resistant alloy metal plate 13a and a heat insulating material 13b such as ceramics laminated on the lower surface. The container body 2 includes a partition plate 14 made of a heat-resistant alloy provided between the heating plate 12 and the heat insulating plate 13. In addition, a combustion chamber 15 is provided in the central portion of the vessel body 2, and a supply air stream connected to the air supply joint 3 that supplies a premixed gas to the combustion chamber 15 between the heat insulating plate 13 and the partition plate 14. A passage 16 is provided, and an exhaust passage 17 connected to the exhaust joint 4 is provided between the heating plate 12 and the partition plate 14 and the combustion gas generated by the combustion of the premixed gas in the combustion chamber 15 flows. It has been. Further, the combustion chamber 15 is divided into two parts, a part on the heat insulating plate 13 side and a part on the heating plate 12 side, by the partition plate 14, and the two parts are communicated with the partition plate 14. A communication hole 18 having a smaller area than the cross-sectional area is formed. A spark plug 19 is inserted into the combustion chamber 15 from the heat insulating plate 13 side, and the premixed gas is ignited by spark discharge of the spark plug 19.

  Here, the premixed gas is preheated by heat exchange with the combustion gas via the partition plate 14, and combustion continues even in the small combustion chamber 15. Further, since the combustion chamber 15 is throttled in the middle by the communication hole 18 formed in the intermediate partition plate 14, the premixed gas flowing into the portion on the heat insulating plate 13 side of the combustion chamber 15 from the air supply passage 16 heats the combustion chamber 15. It is possible to prevent a short circuit from flowing into the exhaust passage 17 through the portion on the plate 12 side. Thereby, the residence time of the premixed gas in the combustion chamber 15 is ensured, and combustion is stabilized.

  Further, since the combustion gas flows through the exhaust passage 17 between the heating plate 12 and the partition plate 14 without touching the heat insulating plate 13, the heat insulating plate 13 is not heated by the combustion gas and passes through the heat insulating plate 13. The heat release of the combustion gas can be easily prevented. Further, since the premixed gas flows through the air supply passage 16 between the heat insulating plate 13 and the partition plate 14 without touching the heating plate 12, the heating plate 12 is heated to a high temperature without taking heat away from the premixed gas. In addition, in combination with the ability to prevent the heat loss of the combustion gas through the heat insulating plate 13, the object to be heated can be heated with high efficiency.

  Further, since the air supply passage 16 and the exhaust passage 17 are separated in the axial direction by the partition plate 14, the premixed gas flowing through the air supply passage 16 leaks into the exhaust passage 17 before the combustion chamber 15. Incomplete combustion due to premixed gas leakage can be reliably prevented. Furthermore, since the spark plug 19 is inserted from the heat insulating plate 13 side, it is possible to prevent the cord for the spark plug 19 from being damaged by heat.

  Here, the air supply passage 16 and the exhaust passage 17 are each formed in a spiral shape with the combustion chamber 15 as the center. In detail, as shown in FIG. 3, double spiral guide walls 20 and 20 that are in contact with the heat insulating plate 13 are integrally formed on the lower surface of the partition plate 14. The lower edge of at least the outermost circumferential portion of the guide wall 20 is airtightly brazed or welded to the heat insulating plate 13. As a result, double spiral air supply passages 16, 16 formed by a gap between the guide walls 20, 20 are formed between the heat insulating plate 13 and the partition plate 14. In addition, a pair of premixed gas inflow portions 15a to the combustion chamber 15 are provided at a downstream end of both the air supply passages 16 and 16 in a point-symmetrical positional relationship. The upstream ends of both the air supply channels 16, 16 are connected to the air supply joint 3. Thus, the premixed gas from the air supply joint 3 flows into the combustion chamber 15 from both the inflow portions 15a and 15a via the both air supply passages 16 and 16, and the swirling flow of the premixed gas into the combustion chamber 15 Is produced. Therefore, the residence time of the premixed gas in the combustion chamber 15 is ensured and mixing is promoted, contributing to stable combustion.

  Each inflow portion 15a needs to be formed so that the width of the inflow portion 15a is equal to or less than the extinguishing distance in order to prevent backfire from the combustion chamber 15 to the air supply passage 16. Here, when the number of inflow portions 15a is one, when the supply flow rate of the premixed gas is increased, the flow rate of the premixed gas in the inflow portion 15a is increased, and a flame blowing phenomenon is likely to occur. On the other hand, if two inflow portions 15a are provided as in the present embodiment, the flow rate of the premixed gas in each inflow portion 15a decreases due to an increase in the total area of the inflow portions 15a, and the occurrence of a flame blowing phenomenon occurs. Is prevented. Further, if there is one inflow portion 15a, there is a possibility that the premixed gas flows in a part in the combustion chamber 15. However, by providing two inflow portions 15a, the premixing in the combustion chamber 15 is possible. The gas flow becomes uniform, which also contributes to the stability of combustion. The number of inflow portions 15a may be three or more.

  In the present embodiment, a recess 13 c is formed on the inner surface of the heat insulating plate 13 so as to surround the insertion location of the spark plug 19. As a result, the premixed gas tends to stay in the vicinity of the spark plug 19 and the ignitability is improved.

  As shown in FIG. 4, double spiral guide walls 21 and 21 that are in contact with the heating plate 12 are integrally formed on the upper surface of the partition plate 14. The upper edge of at least the outermost peripheral portion of the guide wall 21 is airtightly brazed or welded to the heating plate 12. Thereby, between the heating plate 12 and the partition plate 14, double spiral exhaust passages 17 and 17 constituted by a gap between the guide walls 21 and 21 are formed. A pair of combustion gas outflow portions 15b from the combustion chamber 15 are provided at the upstream ends of the exhaust passages 17 and 17 in a point-symmetrical positional relationship. The downstream ends of both the exhaust passages 17, 17 are connected to the exhaust joint 4.

  If the exhaust flow path 17 is formed in a spiral shape in this way, the flow path length of the exhaust flow path 17 is increased, the contact time of the combustion gas with the heating plate 12 is also ensured, and the heating plate 12 is efficiently heated. The

  Here, the direction of the vortex in the air supply channel 16 and the direction of the vortex in the exhaust channel 17 are opposite to each other. More specifically, the air supply passage 16 is a spiral swirling in the clockwise direction from the outside toward the combustion chamber 15 as shown in FIG. 3, while the exhaust passage 17 is as shown in FIG. A spiral swirling counterclockwise from the outside toward the combustion chamber 15, that is, a swirl swirling clockwise from the combustion chamber 15 toward the outside. According to this, the combustion gas swirling in the clockwise direction generated in the combustion chamber 15 by the combustion of the premixed gas flowing while swirling clockwise from the supply air flow path 16 to the combustion chamber 15 smoothly without changing the swirling direction. It flows out from the combustion chamber 15 to the exhaust passage 17 and the passage resistance decreases. Therefore, the blower 6 of the air supply device 5 only needs to have a relatively small capacity.

  In the first embodiment, the air supply channel 16 is formed in a double spiral shape, but the air supply channel 16 may be formed in a simple spiral shape as in the second embodiment shown in FIG. good. In this case, only the downstream end portion of the air supply passage 16 is branched into a double spiral shape by the partition wall 20a, so that two inflow portions 15a of the premixed gas to the combustion chamber 15 are provided as in the first embodiment. be able to. Further, the exhaust passage 17 can also be formed in a simple spiral like the air supply passage 16. In this case, the outflow part 15b of the combustion gas from the combustion chamber 15 to the exhaust passage 17 can be formed larger, unlike the inflow part 15a whose area is limited to prevent backfire. Therefore, it is not necessary to divide the upstream end portion of the exhaust passage 17 into a double spiral and provide two outflow portions 15b.

  Thus, if the air supply flow path 16 and the exhaust flow path 17 are formed in a simple spiral shape, the flow width of the air supply flow path 16 and the exhaust flow path 17 is wider than that of the first embodiment, and the passage The resistance is reduced and the capacity of the blower 6 is smaller. On the other hand, the total flow path length of the air supply flow path 16 and the exhaust flow path 17 becomes shorter than that of the first embodiment, which may cause insufficient preheating of the premixed gas.

  Therefore, in the third embodiment shown in FIG. 6, the side wall (lower surface) of the partition plate 14 facing the heat insulating plate 13 is positioned within the flow path width of the spiral air supply flow channel 16, The fin portions 14a are integrally projected so that a gap is provided between them, and the side surface (upper surface) facing the heating plate 12 of the partition plate 14 is positioned within the flow path width of the spiral exhaust flow path 17. The fin portion 14b is integrally projected so that a gap is left between the heating plate 12 and the heating plate 12. According to this, the heating efficiency of the premixed gas by the combustion gas is enhanced by the fin portions 14a and 14b. Therefore, in order to reduce the passage resistance, the premixed gas can be sufficiently preheated by the combustion gas even if the width of the air supply flow path 16 or the exhaust flow path 17 is increased. It is also possible to project only one of the fin portions 14a and 14b on the partition plate 14.

  Further, as in the fourth embodiment shown in FIG. 7, the inner surface facing the partition plate 14 of the heating plate 12 is positioned within the flow channel width of the spiral exhaust channel 17, and the partition plate 14 The fin portions 12a may be integrally projected so that a gap is left between them. According to this, the heating efficiency of the heating plate 12 by combustion gas is improved by the fin part 12a. Accordingly, in order to reduce the passage resistance, the heating plate 12 can be efficiently heated by the combustion gas even when the exhaust passage 17 is wide. Furthermore, in 4th Embodiment, the fin part 17a similar to 3rd Embodiment is protrudingly provided in the lower surface of the partition plate 17, and premixed gas is preheated efficiently.

  As described above, the embodiment in which the supply air flow channel 16 and the exhaust flow channel 17 are formed in a spiral shape has been described. However, the supply air flow channel 16 is radially formed around the combustion chamber 15 as in the fifth embodiment shown in FIG. It may be formed. More specifically, in the fifth embodiment, an annular wall 22 that surrounds the space between the heat insulating plate 13 and the middle partition plate 14 is integrally formed on the lower surface of the middle partition plate 14. A premixed gas is allowed to flow into the enclosure wall 22 from the air supply joint 3. A plurality of guide walls 20 ′ are integrally formed radially on the lower surface of the partition plate 14 from the surrounding wall 22, and a plurality of air supply airflows are radially formed by gaps between the guide walls 20 ′. A path 16 is formed. A plurality of premixed gas inflow portions 15 a to the combustion chamber 15 are provided at the radially inner ends of the radial air supply passages 16.

  According to this, even if the area of each inflow part 15a is limited to prevent backfire, the total area of the inflow part 15a increases, the flow velocity of the premixed gas in each inflow part 15a decreases, and the flame The occurrence of the blow-off phenomenon is prevented. Moreover, the premixed gas from each inflow part 15a collides with the center part of the combustion chamber 15, and the stagnation point where the flow velocity becomes almost zero is formed, and ignition is easy. Furthermore, the flow of the premixed gas in the combustion chamber 15 becomes uniform, and the combustion is stabilized.

  When the air supply channel 16 is formed radially as described above, the exhaust channel 17 may be formed in the same radial manner, but the exhaust channel 17 is formed in a spiral shape so that only the air supply channel 16 is formed. It is also possible to form them radially. Further, when the air supply passage 16 and the exhaust passage 17 are formed radially, fin portions 14a and 14b are protruded from the partition plate 14 in the same manner as in the third and fourth embodiments. By providing the fin portion 12a on the heating plate 12, the premixed gas and the heating plate 12 can be efficiently heated by the combustion gas without reducing the width of the air supply passage 16 and the exhaust passage 17 so much. become able to.

  In the above embodiment, the guide walls 20, 20 ′, 21 that form the air supply flow path 16 and the exhaust flow path 17 in a spiral shape or a radial shape are integrally formed on the partition plate 14. The guide wall 21 may be formed integrally with the heating plate 12. Furthermore, the guide walls 20 and 20 ′ for the air supply passage 16 and the guide wall 21 for the exhaust passage 17 are divided into the partition plate 14 and the heating plate. These guide walls 20, 20 ′, and 21 can be interposed between the heat insulating plate 13 and the heating plate 12 and the partition plate 14 as a separate body.

The top view of the combustion heater of 1st Embodiment of this invention. The II-II line cutting | disconnection front view of FIG. FIG. 3 is a plan view taken along line III-III in FIG. 2. The IV-IV line cutting | disconnection top view of FIG. The cutting top view corresponding to FIG. 3 of the combustion heater of 2nd Embodiment. The cutting | disconnection front view corresponding to FIG. 2 of the combustion heater of 3rd Embodiment. The cutting | disconnection front view corresponding to FIG. 2 of the combustion heater of 4th Embodiment. The cutting top view corresponding to FIG. 3 of the combustion heater of 5th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Combustion heater, 2 ... Body, 12 ... Heating plate, 12a ... Fin part, 13 ... Heat insulation board, 14 ... Partition plate, 14a, 14b ... Fin part, 15 ... Combustion chamber, 15a ... Inflow part, 16 Air supply passage, 17 ... exhaust passage, 18 ... communication hole, 19 ... spark plug.

Claims (9)

A premixed gas is supplied to the combustion chamber in the center and the combustion chamber in a container body whose one side surface is covered with a heating plate for heating the object to be heated and the other side surface is covered with a heat insulating plate. An air supply passage and an exhaust passage through which combustion gas generated by combustion of the premixed gas in the combustion chamber flows are provided, and the premixed gas flowing in the air supply passage is preheated by the heat of the combustion gas flowing in the exhaust passage. In the combustion heater in which the heating plate is heated,
A partition plate provided between the heating plate and the heat insulation plate is provided, an exhaust passage is provided between the heating plate and the partition plate, and an air supply passage is provided between the heat insulation plate and the partition plate. A combustion heater provided, wherein heat exchange between the combustion gas and the premixed gas is performed via an intermediate partition plate.   The combustion chamber is divided into two parts, a part on the heat insulating plate side and a part on the heating plate side, by the partition plate, and is smaller than the cross-sectional area of the combustion chamber that communicates the two parts with the partition plate. The combustion heater according to claim 1, wherein a communication hole having an area is formed.   The combustion heater according to claim 1 or 2, wherein each of the air supply passage and the exhaust passage is formed in a spiral shape with the combustion chamber as a center.   The combustion heater according to claim 3, wherein the direction of vortex in the air supply passage and the direction of vortex in the exhaust passage are opposite to each other.   The combustion heater according to claim 3 or 4, wherein a plurality of premixed gas inflow portions from the supply air flow path to the combustion chamber are provided.   The air supply flow path is formed radially with the combustion chamber as the center, and a plurality of premixed gas inflow portions to the combustion chamber are provided at the radial inner ends of the radial air supply flow paths. The combustion heater according to claim 1 or 2, characterized by the above.   The air supply channel and the exhaust channel are each formed in a spiral shape or a radial shape centering on the combustion chamber, and are side surfaces of the partition plate facing at least one of the heating plate and the heat insulating plate. In addition, the fin portion is positioned within the flow path width of the air supply flow path or the exhaust flow path formed between the one plate and the partition plate so that a gap is left between the one plate and the air flow path. The combustion heater according to claim 1, wherein the combustion heater is protruded.   The exhaust passage is formed in a spiral shape or a radial shape centering on the combustion chamber, and is located on the inner surface of the heating plate facing the partition plate within the flow passage width of the exhaust passage. The combustion heater according to claim 1, wherein a fin portion is provided so as to leave a gap therebetween.   The combustion heater according to any one of claims 1 to 8, wherein a spark plug is inserted into the combustion chamber from the heat insulating plate side.

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