JP2010078295A - Combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress generation of white smoke from an exhaust port of a combustion device equipped with a latent heat recover heat exchanger. <P>SOLUTION: The combustion device is provided with a main heat exchanger 4 absorbing sensible heat in combustion gas of a burner 1, the latent heat recovery heat exchanger 6 recovering latent heat of exhaust gas, and a combustion fan 5, and one part of air introduced into a combustion chamber 20 during driving of the fan 5 is sent upstream along an inner wall 11 of the combustion chamber 20 to form an air curtain 10 of an air current. A guide part 7 guiding at least one part of the air current of the air curtain 10 to a side of the latent heat recovery heat exchanger 6 through a side part of a positioned area of the main heat exchanger 4 so as to not mix it with the combustion gas, and guiding it to a side of the exhaust port 8 through a side part of a positioned area of the latent heat recovery heat exchanger 6 is formed via an interval with the inner wall 11. Air guided by the guide part 7 to the exhaust port side is mixed and exhausted with the combustion gas having passed through the positioned area of the latent heat recovery heat exchanger 6 to be exhausted from the exhaust port side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a latent heat recovery type combustion apparatus such as a water heater or a bath tub.

  FIG. 5 schematically shows an example of a water heater that is a combustion apparatus. This hot water heater is an outdoor arrangement type hot water heater, and the burner 1 is disposed in the combustion chamber 20 provided in the instrument case 40, and the burner 1 is a fuel supply passage for supplying fuel to the burner 1. A gas pipe 42 is connected. The gas pipe 42 controls an open / close valve (not shown) for controlling supply / stop of fuel to the burner 1 and the amount of fuel supplied to the burner 1 with the valve opening. A proportional valve (not shown) is provided.

  A combustion fan 5 that supplies and exhausts combustion of the burner 1 is provided below the burner 1. As indicated by the arrows in FIG. 1, this water heater supplies air that is sucked in from the outside through the intake port 9 to the burner 1 by the rotation of the combustion fan 5, and is supplied through this air and the gas pipe 42. The combustion gas generated by the burner combustion is sent to the exhaust port 8 side from the combustion chamber 20 by the rotation of the combustion fan 5 and exhausted.

  A main heat exchanger (primary heat exchanger) 4 for recovering sensible heat in the combustion gas of the burner 1 is provided on the upper side of the burner 1, and the flow of the combustion gas is more than that of the main heat exchanger 4. A latent heat recovery heat exchanger (secondary heat exchanger) 6 for recovering the sensible heat and latent heat of the combustion gas is provided on the downstream side (here, the upper side of the main heat exchanger 4).

  The main heat exchanger 4 has a pipe 12 through which hot water passes and a plurality of plate-like plates arranged in parallel with each other in the longitudinal direction of the pipe 12 in a manner of projecting to the outer peripheral side of the pipe 12. And fins 13. For example, as shown in FIG. 6, the fins 13 generally have the fins 13 that pass through the fins 13, and the fins 13 are arranged with a plate-like surface substantially perpendicular to the ducts 12. .

  Further, as shown in FIG. 5, the latent heat recovery heat exchanger 6 is also spaced apart from each other in the longitudinal direction of the pipeline 2 in such a manner that the pipeline 2 through which hot water passes and the outer circumference of the pipeline 2 are projected. And a plurality of plate-like fins 3 arranged in parallel. In this example, also in the heat exchanger 6 for recovering latent heat, the pipe line 2 passes through the fins 3, and the fins 3 are arranged with the plate-like surface in a direction substantially perpendicular to the pipe line 2. However, in recent years, heat exchangers for recovering latent heat that do not have fins 3 (for example, a type in which a large number of thin tubes are arranged, or a tube with an increased surface area of a tube, such as a flexible tube) An equipped combustion device has also been developed.

  Under the latent heat recovery heat exchanger 6, an appropriate drain discharge means for discharging the drain generated in the latent heat recovery heat exchanger 6 to the outside is provided. In the water heater shown in this figure, a drain tray 48 and a drain pipe 49 connected to the tray 48 are provided as drain discharge means. The leading end side of the drain pipe 49 is led out of the instrument case 40 (for example, the lower side of the water heater), and the condensed water droplets (drain drainage) accumulated in the tray 48 are discharged to the outside through the drain pipe 49. It has become.

  Since the drainage is acidic because it contains nitrogen oxides (NOx) in the combustion gas, the drain discharge means is provided with a drain neutralization means 50 for neutralizing the drainage (drain). It has been. For example, in order to neutralize the drain, granulated calcium carbonate or the like is used, and the drainage wastewater becomes neutral calcium nitrate by reacting with the calcium carbonate.

  A water supply pipe 46 for guiding water from a water supply source is connected to the inlet side of the latent heat recovery heat exchanger 6, and the main heat exchanger 4 is connected to the outlet side of the latent heat recovery heat exchanger 6. The entrance side is connected. A hot water supply pipe 47 is connected to the outlet side of the main heat exchanger 4.

  Normally, the water supply pipe 46 includes a water thermistor (not shown) for detecting the temperature of water supplied from the water supply pipe 46 and flowing into the latent heat recovery heat exchanger 6, and the latent heat recovery heat exchanger 6. A water amount sensor (not shown) for detecting the flow rate of water flowing into the hot water supply pipe 47 is provided, and a hot water thermistor (not shown) capable of detecting the temperature of the hot water flowing out is provided in the hot water supply pipe 47. Yes.

  Moreover, the heat of the burner 1 is very high, and the inside of the combustion chamber 20 is also very high. For example, the temperature of the inner cylinder (inner wall) of the combustion chamber 20 rises upon receiving flame radiation of about 1700 ° C. from the burner, but the inner cylinder (inner wall) of the combustion chamber 20 is made of copper, and receives this radiant heat to burn. When the temperature is sometimes high, stress corrosion cracking occurs due to the temperature difference from the non-combustion time. Therefore, in order to protect against this heat, in the combustion apparatus, generally, a part (about 10 to about 30%) of air introduced into the combustion chamber 20 when the combustion fan 5 is driven is indicated by an arrow A in FIG. As shown, an air curtain (side flow) 10 is formed that flows upward along the inner wall 11 of the side wall surface of the combustion chamber 20 and travels to the lower end of the arrangement region of the main heat exchanger 4. The structure which performs is provided.

  For example, as shown in FIG. 7, the air curtain 10 is generally formed to flow upward along the inner walls 11 of the four side walls of the combustion chamber 20, but the burner 1 and the inner wall 11 are separated from each other. When the inner wall 11 on the side wall surface of the combustion chamber 20 is not easily affected by the combustion heat of the burner 1, the inner wall 11 is formed along the inner wall 11 of three or less side wall surfaces excluding the inner wall 11 on the side wall surface. Some are.

  In a combustion apparatus such as a water heater, the combustion control of the burner 1 and the rotation control of the combustion fan 5 are given in advance by combustion control means provided in a control device (not shown) based on the detection signals of the sensors. As described above, the burner 1 is combusted by the gas supplied from the gas pipe 42 and the air sent by the combustion fan 5, so that the latent heat is recovered from the water supply pipe 46. Hot water produced through the heat exchanger 6 and the main heat exchanger 4 in this order is led to a hot water supply place such as a kitchen via a hot water supply pipe 47 to be discharged.

  In the water heater provided with the latent heat recovery heat exchanger 6 as shown in FIG. 5, the water passing through the water pipe in the latent heat recovery heat exchanger 6 from the water supply pipe 46 is generated by the combustion gas due to the combustion of the burner 1. When passing through the heat exchanger for recovery 6, the latent heat possessed by the water vapor in the combustion gas is removed (recovering the latent heat) to increase the temperature, and when passing through the main heat exchanger 4, the burner 1 Since hot water having a set temperature is produced by being heated by the combustion fire power, efficient heating can be performed by the burner 1.

  That is, by providing the heat exchanger 6 for recovering latent heat, for example, in a water heater, the thermal efficiency reaches about 90% or more on a high heating value (total heating value) basis, and the heat exchanger 6 for recovering latent heat is provided. High thermal efficiency is achieved compared to a normal water heater without. Therefore, in recent years, the demand for a combustion apparatus such as a water heater equipped with a heat exchanger 6 for recovering latent heat has been increasing, and not only a new combustion apparatus but also a replacement of a combustion apparatus depending on the life of the combustion apparatus, etc. In addition, a combustion apparatus including a heat exchanger 6 for recovering latent heat has been applied.

  By the way, the exhaust gas of the combustion apparatus such as the hot water heater is exhausted from the exhaust port 8 in a state where the heat is taken away by the latent heat recovery heat exchanger 6, so that the temperature is relatively low at about 50 to 80 ° C. The humidity is almost 100%. Therefore, when the exhaust gas is rapidly cooled outside the apparatus, the combustion product water contained in the exhaust gas reaches the dew point and is dewed. Especially, in the winter, the external temperature is, for example, 5 to 10 ° C. In such a low case, there is a problem that white smoke (water vapor) is generated from the exhaust port 8 to give the user an unpleasant feeling.

  Therefore, in order to prevent this white smoke, for example, a combustion device that connects a passage for sucking external air simultaneously with suction of combustion exhaust gas to the outside of the combustion chamber, and forcibly discharges the mixture by mixing combustion exhaust gas and external air, or exhaust gas Has been proposed (for example, see Patent Documents 1 and 2).

Japanese Utility Model Publication No. 57-13945 Japanese Patent Laid-Open No. 2001-254928

  However, in the configuration in which the passage for sucking the external air is provided as in the proposed device, a dedicated passage must be provided outside the combustion chamber, and accordingly, the device configuration is complicated and enlarged. In addition, the air volume of the combustion fan must be increased (for example, about 1.2 times the normal amount) by the amount of external air sucked, which leads to an increase in the size of the combustion fan and an increase in power consumption. Then there was a problem that went.

  Further, in the configuration in which the exhaust gas is reheated, after exhaust heat is taken away by the latent heat recovery heat exchanger and the exhaust temperature is lowered, heat is given to the exhaust gas to raise the exhaust temperature. Will be invited.

  In addition, in apartment buildings such as condominiums, if there are exhaust openings facing the elevator hall or common hallway, etc., an exhaust pipe such as a chimney will be provided to guide the exhaust of the combustion device such as a water heater to the outer wall of the building. However, in this case, the combustion device is of a latent heat recovery type equipped with a heat exchanger for recovering latent heat. In the equipment, in order to prevent pipe corrosion caused by condensation in the exhaust pipe, heat insulation (for example, 100 mm thick) is applied to the exhaust pipe, and the exhaust pipe must be inclined downward so that condensed water does not stay. I must. For this reason, there is a problem that the extension distance of the exhaust pipe is restricted, and the degree of freedom in designing an apartment or the like is lowered.

  Moreover, in an indoor installation type combustion apparatus, as shown to Fig.9 (a), as shown to Fig.9 (b), as shown in Fig.9 (b), the indoor air supply type / outdoor exhaust type which uses the exhaust pipe 32 to take out the exhaust air outdoors, The outdoor air supply / outside air type that uses a double pipe (one is an air supply pipe 35 and the other is an exhaust pipe 32) is required to use a longer chimney (exhaust pipe). In addition, considering the installation of heat insulating material and the gradient of the exhaust pipe in the latent heat recovery type combustion apparatus, the design itself was difficult. In FIG. 9B, the air supply pipe 35 and the exhaust pipe 32 are described in a state where they are arranged side by side in the vertical direction. However, the air supply pipe 35 and the exhaust pipe 32 are usually provided side by side in the horizontal direction. It is done.

  The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to suppress the generation of white smoke from the exhaust port even in a situation where the outside air temperature is low or the outside air humidity is high. An object of the present invention is to provide a combustion apparatus that can increase thermal efficiency without complicating or increasing the size of the apparatus. Further, according to the present invention, in the indoor installation type combustion apparatus, the down slope of the chimney connected to the combustion apparatus can be reduced or zero, and the exhaust gas is discharged outdoors without any restriction on the extension distance of the chimney. Another object of the present invention is to provide a latent heat recovery type combustion apparatus that can maintain the degree of freedom of condominium design.

  In order to achieve the above object, the present invention has the following configuration as means for solving the problems. That is, the first invention provides a burner in the combustion chamber, a main heat exchanger provided above the burner to absorb sensible heat in the combustion gas, and the combustion more than the main heat exchanger. A latent heat recovery heat exchanger that is disposed downstream of the gas flow and recovers exhaust latent heat, and preheats the water that passes through the latent heat recovery heat exchanger with the heat of latent heat recovery. Water is supplied to the water inlet of the main heat exchanger and heated by the main heat exchanger, and outside air is led to the combustion chamber side below the burner and supplied to the burner. An area in which the main heat exchanger is disposed, wherein a combustion fan is provided, and a part of the air introduced into the combustion chamber when the combustion fan is driven flows upward along the inner wall of the side wall surface of the combustion chamber A combustion device that forms an air curtain for the air flow to the lower end of the In order to prevent at least a part of the air flow forming the air curtain from being mixed with the combustion gas, the side portion of the arrangement area of the main heat exchanger is guided to the latent heat recovery heat exchanger side through a side wall. A guide portion that leads to the exhaust port side through the side of the arrangement area of the recovery heat exchanger is formed through an interval with the inner wall of the side wall surface of the combustion chamber, and is guided by the guide portion to the exhaust port side. The air that has been guided to the exhaust gas is mixed with the combustion gas exhausted from the exhaust port side through the arrangement region of the latent heat recovery heat exchanger and exhausted.

  Further, in the second invention, in addition to the configuration of the first invention, the main heat exchanger includes a pipe line through which hot water passes and a longitudinal direction of the pipe line in a mode of projecting to the outer peripheral side of the pipe line And a plurality of plate-like fins arranged in parallel with each other at intervals, the fins being arranged with the plate-like surface in a direction substantially perpendicular to the pipe line, and the proximal end of the guide portion The side is directly or indirectly connected to the fins disposed on one end of the main heat exchanger or the upper ends of the fins disposed on both ends.

  Furthermore, in the third aspect of the invention, in addition to the configuration of the second aspect of the invention, the guide portion is formed with a plate-like member, and the latent heat recovery heat exchanger is located above the main heat exchanger. And a plurality of plate-like fins arranged in parallel with each other in the longitudinal direction of the pipeline in a manner of projecting to the outer peripheral side of the pipeline, The fins are formed in a plate-like surface in a substantially horizontal direction or in a direction inclined obliquely from the horizontal, and the plate-like member of the guide portion whose base end side is connected to the fins of the main heat exchanger is the main heat The latent heat recovery heat is passed through a curved surface portion that bends from a substantially vertical direction, which is an arrangement direction of the fins of the exchanger, to a substantially horizontal direction or an oblique direction, which is an arrangement direction of the fins of the latent heat recovery heat exchanger. The plate member is extended toward the exchanger, and the leading end side of the plate member is the end of the latent heat recovery heat exchanger. Characterized in that it is connected the side of the corresponding directly or indirectly to the end portion of the fin.

  Further, according to a fourth invention, in addition to the configuration of the first, second or third invention, the pipe of the latent heat recovery heat exchanger is formed so as to protrude also from a gap between the guide portion and the side wall of the combustion chamber. It is characterized by being.

  Further, the fifth invention is characterized in that, in addition to the configuration of any one of the first to fourth inventions, CO detection means for detecting carbon monoxide in the pre-combustion gas is provided.

  Further, the sixth invention is an exhaust gas exhaust port provided with a combustion gas exhausted from an exhaust port of the combustion device at a position away from the combustion device in addition to the configuration of any one of the first to fifth inventions. An exhaust pipe connecting portion leading to the exhaust air outlet is provided, and air curtain air passing through a side portion of the arrangement area of the latent heat recovery heat exchanger is provided at the position near the exhaust port for the latent heat recovery. An air rectification unit is provided that guides the combustion gas to the exhaust pipe side in such a manner that the combustion gas passes through the side of the heat exchanger and is guided to the side by the air for the air curtain. It is characterized by being.

  Further, in the seventh invention, in addition to the configuration of the sixth invention, a CO detection means for detecting carbon monoxide in the combustion gas is provided downstream of the air rectification unit in the flow of the combustion gas. It is characterized by.

  According to the present invention, a latent heat recovery heat exchanger is provided, and water passing through the latent heat recovery heat exchanger is preheated with latent heat recovery heat, and the preheated water is supplied to the inlet of the main heat exchanger. Therefore, it is possible to provide a highly efficient combustion apparatus as compared with a combustion apparatus that does not have a latent heat recovery heat exchanger.

  Further, the combustion apparatus of the present invention causes a part of the air introduced into the combustion chamber when the combustion fan is driven to flow upward along the inner wall of the side wall surface of the combustion chamber, and the arrangement of the main heat exchanger An air curtain is formed for the air flow toward the lower end of the region, but at least a part of the air flow is not mixed with the combustion gas, and the side portion of the arrangement region of the main heat exchanger is passed through a trap for the latent heat recovery. A guide portion that leads to the heat exchanger side and leads to the exhaust port side through the side of the arrangement region of the latent heat recovery heat exchanger is formed with a gap from the inner wall of the side wall surface of the combustion chamber.

  In general, the combustion gas exhausted through the arrangement region of the latent heat recovery heat exchanger has a humidity of about 100%. In the present invention, the combustion gas is guided by the guide portion and guided to the exhaust port side. Since the air is guided to the exhaust port side so as not to be mixed with the combustion gas, the humidity is low.

  In the present invention, the air is mixed with the combustion gas exhausted from the exhaust port side through the arrangement region of the latent heat recovery heat exchanger and exhausted, so the humidity of the combustion gas exhausted from the exhaust port side is exhausted. Even if this exhaust gas is discharged to the outside of the device, the combustion generated water contained in the exhaust gas does not reach the dew point, and condensation can be prevented, and white smoke (water vapor) accompanying condensation is discharged. Problems such as coming out of the mouth can be suppressed. Further, according to the present invention, since the humidity of the exhaust gas can be lowered as described above, the efficiency of the combustion apparatus can also be improved.

  Furthermore, the present invention utilizes the air flow introduced into the combustion chamber to form an air curtain to prevent white smoke as described above and improve the efficiency of the combustion apparatus. There is no need to newly form a dedicated passage to be introduced outside the combustion chamber, and there is no need to increase the air volume of the combustion fan, which can suppress an increase in the size and cost of the apparatus.

  Furthermore, the heat exchanger for recovering latent heat needs to be formed using a metal that is resistant to corrosion, such as SUS316L (SUS316L is JIS standard). Conventionally, a high-temperature (high energy density) exhaust gas and air are used. Heat was exchanged by mixing air for curtains (low energy density), so the surface area of the latent heat recovery heat exchanger could be increased in order to recover sufficient latent heat with the latent heat recovery heat exchanger. It was necessary. Since the metal resistant to corrosion is expensive, the conventional latent heat recovery type combustion apparatus (with a heat exchanger for recovering latent heat) that must use a large amount of the metal should reduce the cost accordingly. It was difficult.

  On the other hand, the present invention is configured to mix air curtain air with the combustion gas after passing through the arrangement region of the latent heat recovery heat exchanger. Since the latent heat can be directly recovered from the gas, the latent heat can be recovered with high efficiency even if the surface area of the heat exchanger for recovering latent heat is smaller than that of the conventional combustion apparatus. Therefore, the amount of metal that is resistant to corrosion as described above but is expensive can be reduced, and the cost of the combustion apparatus can be reduced.

  Further, in the present invention, the plurality of fins formed in the main heat exchanger are arranged with the plate-like surface in a direction substantially perpendicular to the pipe line of the main heat exchanger, and the proximal end of the guide portion According to the configuration in which the side is directly or indirectly connected to the fins disposed on one end side of the main heat exchanger or the upper ends of the fins disposed on both end sides, the main heat exchanger The guide portion can be easily attached using the fins. Therefore, the combustion apparatus which can exhibit the said effect with a simpler structure can be formed.

  Furthermore, in the present invention, the fins of the heat exchanger for latent heat recovery arranged above the main heat exchanger are formed in a direction in which the plate-like surface is inclined substantially horizontally or obliquely from the horizontal, and the base end The plate-like member of the guide portion, the side of which is connected to the fins of the main heat exchanger, is disposed in the fins of the heat exchanger for latent heat recovery from a substantially vertical direction that is the arrangement direction of the fins of the main heat exchanger. The plate member is extended toward the latent heat recovery heat exchanger through a curved surface portion that is bent in a substantially horizontal direction or an oblique direction, and the front end side of the plate member is an end portion of the latent heat recovery heat exchanger. According to the configuration that is directly or indirectly connected to the end of the corresponding fin on the side, the guide portion that efficiently guides the air flow that forms the air curtain to the exhaust port side is connected to the main heat exchanger. Using fins and fins of latent heat recovery heat exchanger It can be attached to.

  Furthermore, in the present invention, according to the configuration in which the pipe line of the heat exchanger for recovering latent heat is formed so as to extend over the space between the guide portion and the side wall of the combustion chamber, the pipe line formed with this overhanging also burns. Since latent heat can be recovered from air curtain air that has been warmed by the radiation heat of the gas, the efficiency of the combustion apparatus can be further increased.

  Further, in the present invention, in the case where CO detecting means for detecting carbon monoxide during combustion is provided, when carbon monoxide is generated due to incomplete combustion of the burner, etc., carbon monoxide in the combustion gas Can be detected by the CO detection means, so that the detection result can be used to warn the generation of carbon monoxide or to stop the water heater from burning by using a safety device. Safety can be increased.

  Furthermore, in the present invention, an exhaust pipe connecting portion is provided, and an air rectifying portion is provided at a position near the exhaust port so as to guide the combustion gas to the exhaust pipe side in a form of being wrapped with air curtain air. In what is being done, because of the effect of air curtain air in a manner that encloses the combustion gas, the exhaust pipe temperature can be lowered compared to a configuration in which the combustion gas and air curtain air are exhausted in a mixed state, There is no need to wrap the exhaust pipe connected to the combustion device with a heat insulating material such as glass wool. Therefore, the cost associated with the installation of the combustion apparatus can be reduced, and in particular, in an indoor installation type combustion apparatus, it is possible to eliminate the need for a heavy work of insulating the insulation material such as glass wool around the exhaust pipe in a narrow ceiling. The construction work can be simplified, and the down slope of the exhaust pipe can be made small or zero, so that the degree of freedom in designing an apartment or the like can be maintained.

  Furthermore, in the present invention, the air rectifying unit is provided, and CO detection means for detecting carbon monoxide in the combustion gas is provided downstream of the air rectification unit in the flow of the combustion gas. In addition to the effect of the air rectification unit, when carbon monoxide is generated due to incomplete combustion of the burner, etc., carbon monoxide in the combustion gas can be detected by the CO detection means. It is possible to warn the generation of carbon monoxide and to stop the combustion of the water heater by using a safety device, thereby improving the safety of the combustion device. The combustion gas that is led to the exhaust side through the air rectifier is led to the exhaust port side in a mode of being wrapped in the air curtain air, but part of the combustion gas is mixed with the air curtain air. become.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the present embodiment, the same reference numerals are assigned to the same name portions as those in the conventional example, and the duplicate description is omitted or simplified.

  FIG. 1 schematically shows the configuration of a first embodiment of a combustion apparatus according to the present invention. As shown in the figure, the combustion apparatus of the present embodiment is an outdoor installation type (outdoor type) provided with a main heat exchanger 4 and a latent heat recovery heat exchanger 6 as in the conventional example shown in FIG. This is a water heater of the installation type, and is provided with a combustion fan 5 on the lower side of the burner 1, and is configured to form an air curtain 10 when the combustion fan 5 is driven.

  What is different from the conventional example is that the present embodiment has a guide portion 7 formed at a distance from the inner wall 11 of the side wall surface of the combustion chamber 20. As shown by an arrow B, the guide portion 7 has a side portion in the arrangement region of the main heat exchanger 4 so that at least a part of the air flow forming the air curtain 10 is not mixed with the combustion gas. The latent heat recovery heat exchanger 6 is led to the latent heat recovery heat exchanger 6 side, and the side portion of the arrangement area of the latent heat recovery heat exchanger 6 is led to the exhaust port 8 side through the trap. In this embodiment, the guide portion 7 The combustion gas exhausted from the exhaust port 8 side through the arrangement area of the latent heat recovery heat exchanger 6 (arrow C) is guided by the guide portion 7 and guided to the exhaust port side. It is characterized by being mixed and exhausted.

  The guide portion 7 is formed along the inner walls 11 of the two side wall surfaces on the left and right sides of the four inner wall surfaces 11 of the combustion chamber 20 except for the front side and the rear side in the figure. It has the plate-shaped member provided in the same direction as the direction of the fin 13 of the exchanger 4. The base end side of the guide part 7 is indirectly connected to the upper end part of each fin 13 arrange | positioned at the both ends of the said main heat exchanger 4 via the packing 16, as shown in FIG. ing. Note that the guide portion 7 may be directly connected to the fin 13 without using the packing 16, and in this case, the guide portion 7 can be connected and fixed using solder, silver gutter, or the like. The guide part 7 can be connected to

  Further, in the present embodiment, the pipe line 2 of the latent heat recovery heat exchanger 6 is formed so as to protrude from the gap between the guide portion 7 and the side wall of the combustion chamber 20.

  The present embodiment is configured as described above, and as with the conventional example, with the combustion of the burner 1, water passing through the main heat exchanger 4 and the latent heat recovery heat exchange 6 is heated to supply hot water. In this burner combustion, the air curtain 10 is formed. In this embodiment, as described above, the air curtain 10 is provided with the characteristic guide portion 7. In order to prevent at least a part of the air flow forming the gas from being mixed with the combustion gas, the side portion of the arrangement area of the main heat exchanger 4 is led to the latent heat recovery heat exchanger 6 side through the side wall, and further, the latent heat recovery heat exchange is performed. The side of the arrangement area of the heat generator 6 is led to the exhaust port 8 side through the trap, and this air flow is mixed with the combustion gas exhausted from the exhaust port 8 through the arrangement area of the latent heat recovery heat exchanger 6. And exhaust.

  Usually, the combustion gas exhausted through the arrangement region of the latent heat recovery heat exchanger 6 has a humidity of about 100%, whereas the air guided by the guide portion 7 and led to the exhaust port side. Is guided to the exhaust port side so as not to be mixed with the combustion gas, so that the humidity is low, and this air passes through the arrangement area of the latent heat recovery heat exchanger 6 and is exhausted from the exhaust port 8 side. When mixed and exhausted, the humidity of the combustion gas exhausted from the exhaust port 8 side can be lowered.

  Therefore, even if this exhaust gas is discharged to the outside of the device, the combustion product water contained in the exhaust gas does not reach the dew point, so that condensation can be prevented, and white smoke (water vapor) accompanying the condensation is on the exhaust port side. You can control problems such as getting out of Further, since the humidity of the exhaust gas can be lowered, the efficiency of the combustion apparatus can also be improved.

  In addition, according to the present embodiment, the air flow introduced into the combustion chamber 20 to form the air curtain 10 is used to prevent white smoke as described above and improve the efficiency of the combustion apparatus. There is no need to newly form a dedicated passage for taking in air and introducing it to the exhaust side, and there is no need to increase the air volume of the combustion fan 5, leading to an increase in the size and cost of the apparatus. Can be suppressed.

  Further, according to this embodiment, the plurality of fins 13 formed in the main heat exchanger 4 have a plate-like surface substantially perpendicular to the pipe line 12 of the main heat exchanger 4. And the base end side of the guide portion 7 is connected to the upper end portions of the fins 13 disposed on both end sides of the main heat exchanger 4, and the fins 13 of the main heat exchanger 4 are used. The guide part 7 can be easily attached. Therefore, the combustion apparatus which can exhibit the said effect with a simpler structure can be formed.

  Furthermore, according to the present embodiment, the pipe line 2 of the latent heat recovery heat exchanger 6 is formed so as to protrude from the gap between the guide portion 7 and the side wall of the combustion chamber 20. Since the latent heat of the combustion gas can be recovered also by the pipe line 2, the efficiency of the combustion apparatus can be further enhanced.

  FIG. 3 shows a water heater of a second embodiment of the combustion apparatus according to the present invention, and the same reference numerals are assigned to the same names as those of the first embodiment. Similarly to the first embodiment, the second embodiment is an outdoor water heater and is configured to have a characteristic guide portion 7. However, the second embodiment is for latent heat recovery. The arrangement of the heat exchange 6 is different from that of the first embodiment, and accordingly, the formation of the guide portion 7 is different from that of the first embodiment.

  That is, in the second embodiment, the latent heat recovery heat exchanger 6 disposed on the upper side of the main heat exchanger 4 has the fins 3 formed in a direction in which the plate-shaped surface is inclined obliquely from the horizontal. ing. Then, the plate-like member of the guide portion 7 whose base end side is connected to the fins 13 of the main heat exchanger 4 is the latent heat recovery heat from the substantially vertical direction that is the direction in which the fins 13 of the main heat exchanger 4 are arranged. The plate 6 is extended toward the latent heat recovery heat exchanger 6 through a curved surface portion 15 bent in an oblique direction, which is the direction in which the fins 3 are arranged, and the front end side of the plate-like member is for latent heat recovery. The heat exchanger 6 is directly or indirectly connected to the end of the corresponding fin 3 on the end side.

  In FIG. 4, the formation mode of the guide portion 7 of the second embodiment is schematically shown in a perspective view.

  The present embodiment is configured as described above, and can achieve the same effects as the first embodiment. Further, in the second embodiment, the guide portion 7 is configured as described above, whereby the air flow forming the air curtain can be efficiently guided to the exhaust port side, and the guide portion 7 has the main heat. Since the fins 13 of the exchanger 4 and the fins 3 of the latent heat recovery heat exchanger 6 can be easily attached, a water heater that exhibits the above-described excellent effects can be easily formed.

  FIG. 8 shows a water heater of a third embodiment of the combustion apparatus according to the present invention. The third embodiment is a water heater installed indoors, and as shown in the figure, a connecting portion 33 for connecting the exhaust pipe 32 is provided protruding from the upper surface side of the appliance case 40. . The exhaust pipe 32 guides the combustion gas discharged from the exhaust port 8 of the water heater to an exhaust gas exhaust port (not shown in FIG. 8) provided at a position away from the water heater. 9 (a) and FIG. 9 (b).

  What is characteristic in the third embodiment is that the air rectifying unit 34 is provided in the vicinity of the exhaust port 8 (the front side of the flow of the combustion gas (exhaust gas) with respect to the connection portion 33 of the exhaust pipe 32). That is. The air rectifying unit 34 moves the air curtain air (see arrow B) through the side of the arrangement area of the latent heat recovery heat exchanger 6 through the arrangement area of the latent heat recovery heat exchanger 6. The combustion gas (see arrow C) that has passed through is guided to the side by the side, and the combustion gas is led to the exhaust pipe side in a manner of wrapping with the air for the air curtain. It is formed by taking a long straight portion (for example, extending the guide portion 7) or the like.

  Thus, by providing the air rectifying unit 34 and rectifying the air used for the air curtain in front of the connecting portion 33 of the exhaust pipe 32, the temperature is about 50 to 80 ° C. and the humidity is about 100%. Exhaust pipe in such a manner that the exhaust gas is enveloped by the air used for the air curtain without sufficiently mixing the exhaust gas and the air used for the air curtain that does not pass through the latent heat recovery heat exchanger 6 32 starts flowing. Therefore, the temperature of the exhaust pipe 32 can be lowered.

  In Article 115, Paragraph 1, Item 3 of the Building Standards Law Enforcement Ordinance, if the exhaust gas temperature in the exhaust pipe (exhaust tube) connected to the indoor water heater exceeds 100 ° C, the temperature is 260. When the temperature is less than or equal to ° C., it is defined that an incombustible heat insulating material having a thickness of 20 mm (millimeters) or more is wound around the exhaust pipe. This is to prevent the high temperature exhaust pipe from causing a fire by directly contacting a material (wall surface) other than the non-combustible material in the concealed portion such as the back of the ceiling. On the other hand, when the exhaust temperature is 100 ° C. or lower, it is not necessary to cover it with a heat insulating material.

  In general, in a water heater, the temperature of the exhaust gas passing through the inside of the latent heat recovery heat exchanger 6 is about 50 to 80 ° C., and this is mixed with the air used for the air curtain and led out from the exhaust port 8. As a matter of course, since the exhaust temperature is 100 ° C. or lower, it is not necessary to wrap the heat insulating material as in the case where the exhaust temperature exceeds 100 ° C.

  However, if a hot water heater has failed and water is not flowing, it is assumed that high temperature exhaust gas is emitted. Note that the water heater is generally provided with a safety device for stopping the combustion when the above-described failure is detected by an internal temperature fuse or the like. Even in the embodiment, this safety device is provided. However, when the exhaust pipe 32 in the vicinity of the water heater instantaneously exceeds 100 ° C. only for a short time after the failure occurs until the safety device works ( There is a possibility that the exhaust gas in the exhaust pipe 32 exceeds 100 ° C.). Assuming this, in the third embodiment, the air rectifying unit 34 is provided in order to further enhance the safety of the water heater.

  In the third embodiment, by providing the air rectifier 34, the exhaust pipe 32 in the vicinity of the water heater does not become hot as described above, and the temperature of the exhaust gas in the exhaust pipe 32 is Since the exhaust pipe 32 is deprived of heat and becomes lower as the distance from the heater increases, if the temperature of the exhaust pipe 32 in the vicinity of the water heater can be lowered as in the third embodiment, the exhaust pipe 32 is 100 over the entire area. It does not exceed ℃ and can be very safe for fire prevention. Further, since dew condensation of the combustion gas can be prevented (further, the exhaust gas 32 is more reliably passed through the air curtain air in a manner that wraps the combustion gas with the air curtain air), so that a hole is opened in the exhaust pipe 32 due to dew condensation. It is possible to prevent the occurrence of such troubles as well as the danger of exhaust leakage from the hole.

  Further, in the third embodiment, as in the first and second embodiments, the pipe line 2 of the latent heat recovery heat exchanger 6 extends over the gap between the guide portion 7 and the side wall of the combustion chamber 20. Since it is formed, it is possible to recover the latent heat of the combustion gas and to lower the temperature of the air for the air curtain by the overhanging pipe line 2 as well. Therefore, when the exhaust pipe 32 is caused to flow in such a manner that the exhaust gas is wrapped with air for the air curtain, the temperature of the exhaust pipe 32 can be further reduced, and the safety can be further improved.

  Incidentally, the third embodiment is also characterized in that a CO sensor 30 as a CO detection means for detecting carbon monoxide (CO) in the combustion gas is provided on the downstream side of the air rectifying unit 34. It is said. The CO sensor 30 is disposed at a position where the air curtain air that has passed through the air rectifying unit 34 and the combustion gas (exhaust gas) are slightly mixed, and the CO sensor 30 is located at a position on the lower side of the CO sensor 30. Is provided with a diffusion plate 31 for diffusing exhaust gas (exhaust gas) and air curtain air in the region where the CO sensor 30 is disposed (see FIG. 8B).

  In the third embodiment, by providing the CO detection means (CO sensor) 30, even when incomplete combustion of the water heater occurs and carbon monoxide is generated, the generation of CO can be detected. Then, using the detection result, in the third embodiment, it is possible to warn the generation of carbon monoxide and to stop the combustion of the water heater by operating the safety device, so that the safety can be further improved. it can.

  There are several types of CO sensors, such as a catalytic combustion type and a semiconductor type. For example, if the drain dripping from the heat exchanger 6 for recovering latent heat hits the CO sensor, the detection (sensing) of CO is detected. Can not. In addition, the CO detection portion of the CO sensor is covered by condensation, and CO cannot be detected unless the CO contacts the detection portion. Therefore, in a combustion apparatus such as a water heater provided with the heat exchanger 6 for recovering latent heat, it is important to properly arrange the CO sensor, but the third embodiment is an air rectifier. By providing the CO sensor 30 on the downstream side of the section 34, problems associated with the condensation and drain can be avoided, and the carbon monoxide in the combustion gas can be detected appropriately by the CO sensor 30.

  That is, condensation does not drip on the CO sensor 30 and, as described above, the air curtain air that has passed through the air rectifying unit 34 and the combustion gas are slightly mixed, so that the combustion is performed by the air used for the air curtain. Since the humidity of the gas is lowered and the exhaust gas in contact with the CO sensor 30 becomes lower than the humidity at which condensation occurs (for example, close to 100%), problems associated with the condensation can also be avoided. Further, by providing the air rectifying unit 34 and providing the CO sensor 30 on the downstream side thereof, the CO detection concentration of the CO sensor 30 is corrected according to the mixing ratio X of the exhaust gas and the air used for the air curtain. You can also

  In the water heater, the CO sensor 30 is not necessarily disposed at the downstream side of the flow of the combustion gas with respect to the air rectifying unit 34, but between the main heat exchanger 4 and the latent heat recovery heat exchanger 6. The CO sensor 30 can also be installed in this case, but in this case, the drain dripping from the latent heat recovery heat exchanger 6 is dripped onto the main heat exchanger 4 as in the water heater shown in FIG. And the problem by drain dripping arises. Moreover, it is preferable if it has a structure that drops on the opposite side (exhaust side) of the main heat exchanger 4 as in the hot water heater shown in FIG. 3, but the connection port of the exhaust pipe of a general indoor installation type hot water heater Is on the upper surface (top plate) side of the water heater, and when this structure is combined with the structure shown in FIG. 3, the structure becomes too complicated.

  Therefore, in the configuration in which the connection port 33 of the exhaust pipe 32 is provided on the upper surface side of the water heater as in the third embodiment, it is preferable to provide the CO sensor 30 at a position near the exhaust port 8. Even if the CO sensor 30 is disposed in the vicinity of the exhaust port 8, problems due to the condensation of combustion gas can be suppressed by the air curtain air, so that the CO sensor 30 is disposed as shown in FIG. Without applying the configuration shown in FIG. 3, the burner 1, the main heat exchanger 4, the latent heat recovery heat exchanger 6, and the exhaust pipe connection port 33 can be simply arranged.

  In addition, this invention is not limited to the said embodiment, It can take various aspects. For example, in the second embodiment, the fins 3 of the latent heat recovery heat exchanger 6 are provided in a direction inclined obliquely from the horizontal, but the fins 3 may be provided in a substantially horizontal direction. However, it is preferable to provide the fins 3 at an angle as in the second embodiment because the drain can be easily collected.

  Moreover, in each said embodiment, although the base end side of the guide part 7 was connected to the upper end part of each fin 13 arrange | positioned at the both end sides of the main heat exchanger 4, the formation aspect of the guide part 7 is shown. Is not particularly limited, and is set as appropriate. For example, the guide portion 7 may be provided at a distance from the inner wall 11 of one, three, or four side wall surfaces of the combustion chamber 20, and corresponds to one or more surfaces of the formation surface of the air curtain 10. Can be provided.

  In addition, when providing the guide part 7 through the space | interval with the inner wall 11 of one side wall surface of the combustion chamber 20, direction of the base end side of the guide part 7 and the main heat exchanger 4 like the said each embodiment. If the directions of the fins 13 are set in the same direction and the base end side of the guide portion 7 is connected to the upper end portion of the fin 13 disposed on one end side of the main heat exchanger 4, the guide portion 7 can be easily provided. Moreover, if the front end side of the guide part 7 is connected to the fin 3 of the heat exchanger 6 for latent heat recovery, the guide part 7 can be attached more easily.

  Furthermore, in each of the above-described embodiments, the pipe line 2 of the latent heat recovery heat exchanger 6 is formed so as to protrude from the gap between the guide part 7 and the side wall of the combustion chamber 20, but the pipe line 2 is connected to the guide part 7. You may form so that it may not protrude to the space | interval with the combustion chamber 20 and a side wall (namely, it is inside the guide part 7).

  Further, in each of the above embodiments, the latent heat recovery heat exchanger 6 has the fins 3, but the present invention is also applied to a combustion apparatus having the latent heat recovery heat exchange 6 not having the fins 3. Can also be applied.

  Further, in each of the above embodiments, a fin plate is added to the overhanging portion of the latent heat recovery heat exchanger 6 (for example, the latent heat recovery heat exchanger 6 having a large number of thin tubes arranged, a flexible tube, etc. In addition, in the case of a meandering tube with an increased surface area of the tube, increase the contact area so that sufficient cooling is possible), and lower the temperature of the air used for the air curtain Also good.

  Furthermore, in the third embodiment, the air rectifying unit 34 is formed by forming a straight portion of the exhaust gas passage long, but may be formed by using a honeycomb structure or the like.

  Further, the CO sensor 30 as provided in the third embodiment may be provided in the first embodiment and the second embodiment. In this case, the arrangement position of the CO sensor 30 is appropriately set. However, in the first and second embodiments, the air curtain is located downstream of the latent heat recovery heat exchanger 6 in the flow of the combustion gas. If the CO sensor 30 is provided in a region where the working air and the combustion gas are mixed, the carbon monoxide can be detected by the CO sensor 30 without causing problems due to condensation of the combustion gas and drain water. In the case of the second embodiment, the CO sensor 30 may be provided upstream of the flow of combustion gas from the latent heat recovery heat exchanger 6 (downstream from the main heat exchanger 4). Water does not cause a problem in the sensitivity of the CO sensor 30.

  Furthermore, in the latent heat recovery type indoor installation type combustion apparatus of the type connected to the exhaust pipe 32 as in the third embodiment, it may be caused to burn even though water is not passed due to failure. Even in the case where the temperature of the exhaust gas does not exceed 100 ° C., the air rectifying unit 34 may not be provided.

  In addition, even when the temperature of the exhaust gas exceeds 100 ° C. at the time of the failure, the combustion gas exhausted from the exhaust port side through the arrangement area of the latent heat recovery heat exchanger 6 is used for the air curtain. Since the exhaust temperature exceeds 260 ° C. can be avoided by mixing and exhausting air, as in the past, for example, a heat insulating material having a thickness of 100 mm is used for the prevention of condensation and fire prevention. For example, it is not provided because the ceiling height of the condominium is not enough and it is practically impossible to construct, and a 20 mm thick heat insulating material only for fire prevention. Can be installed in the exhaust pipe 32 so that the latent heat recovery type indoor combustion apparatus can be installed.

  Further, in each of the above embodiments, the hot water heater is used. However, the combustion apparatus of the present invention is not limited to the hot water heater, and includes a main heat exchanger 4 and a latent heat recovery heat exchanger 6. It may be a bath pot, or a combined water heater having both functions of a water heater and a bath pot.

  Further, each of the above embodiments is not necessarily a gas combustion type combustion apparatus, but may be an oil combustion type combustion apparatus.

It is a principal part block diagram which shows typically the 1st Embodiment of the combustion apparatus which concerns on this invention. It is explanatory drawing which shows the arrangement | positioning structure by the side of the guide part in the said 1st Embodiment. It is a principal part block diagram which shows typically the 2nd Embodiment of the combustion apparatus which concerns on this invention. It is a perspective view which shows typically the arrangement | positioning form of the guide part in the said 2nd Embodiment. It is explanatory drawing which shows typically an example of the combustion apparatus provided with the heat exchanger for latent heat collection | recovery. It is a perspective view which shows the example of formation of the pipe line and fin which form a heat exchanger. It is explanatory drawing which shows typically the example of formation of the air curtain in a combustion apparatus. It is typical explanatory drawing for demonstrating the 3rd Embodiment of the combustion apparatus which concerns on this invention. It is explanatory drawing which shows typically the installation structure example of the indoor arrangement | positioning type combustion apparatus and the piping connected to the apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Burner 2,12 Pipe line 3,13 Fin 4 Main heat exchanger 5 Combustion fan 6 Heat exchanger for latent heat recovery 7 Guide part 8 Exhaust port 9 Intake port 10 Air curtain 11 Inner wall 15 Curved surface part 16 Packing 30 CO sensor 32 Exhaust pipe 33 Connection 34 Air rectifier

Claims (7)

  In the combustion chamber, a burner, a main heat exchanger provided on the upper side of the burner to absorb sensible heat in the combustion gas, and disposed on the downstream side of the flow of the combustion gas from the main heat exchanger And a latent heat recovery heat exchanger that recovers the latent heat of exhaust, and preheats water passing through the latent heat recovery heat exchanger with latent heat recovery heat, and the preheated water is supplied to the main heat exchanger. A combustion fan is provided on the lower side of the burner to guide the outside air to the combustion chamber side and supply the burner. A part of the air introduced into the combustion chamber when the fan is driven flows upward along the inner wall of the side wall surface of the combustion chamber, and the air flow toward the lower end portion of the arrangement region of the main heat exchanger In the combustion apparatus for forming an air curtain, the air curtain In order to prevent at least a part of the formed air flow from being mixed with the combustion gas, the side portion of the main heat exchanger is guided to the side of the latent heat recovery heat exchanger through a lateral side of the heat exchanger for the latent heat recovery. A guide portion that guides the side portion of the arrangement region to the exhaust port side through a gap is formed through an interval with the inner wall of the side wall surface of the combustion chamber, and guides the air guided to the exhaust port side by the guide portion. A combustion apparatus, wherein the combustion gas is exhausted by being mixed with combustion gas exhausted from an exhaust port side through an arrangement region of the latent heat recovery heat exchanger.   The main heat exchanger has a pipeline through which hot and cold water passes and a plurality of plate-like fins arranged in parallel with each other in the longitudinal direction of the pipeline in a manner of projecting to the outer peripheral side of the pipeline. The fins are arranged with a plate-like surface in a direction substantially perpendicular to the pipe line, and the proximal end side of the guide portion is a fin disposed on one end side of the main heat exchanger or both ends. The combustion apparatus according to claim 1, wherein the combustion apparatus is directly or indirectly connected to an upper end portion of each fin disposed on the side.   The guide portion is formed with a plate-like member, and the latent heat recovery heat exchanger is disposed above the main heat exchanger, and is connected to a pipe line through which hot water passes and an outer peripheral side of the pipe line. A plurality of plate-like fins arranged in parallel with each other in the longitudinal direction of the pipe line in a longitudinal direction, and the fins are in a substantially horizontal direction or in a direction inclined obliquely from horizontal. The plate-like member of the guide portion, which is formed and connected to the fins of the main heat exchanger on the base end side, heats the latent heat recovery heat from a substantially vertical direction that is the direction in which the fins of the main heat exchanger are arranged It is extended toward the latent heat recovery heat exchanger through a curved surface portion bent in a substantially horizontal direction or an oblique direction, which is the direction in which the fins of the exchanger are arranged, and the front end side of the plate-like member is the latent heat recovery side. Connected directly or indirectly to the end of the corresponding fin on the end side of the heat exchanger And combustion apparatus according to claim 2, wherein a has.   The combustion apparatus according to claim 1, 2 or 3, wherein the conduit of the heat exchanger for recovering latent heat is formed so as to protrude from a space between the guide portion and the side wall of the combustion chamber.   The combustion apparatus according to any one of claims 1 to 4, further comprising CO detection means for detecting carbon monoxide in the combustion gas.   There is provided an exhaust pipe connecting portion for leading the combustion gas discharged from the exhaust port of the combustion device to an exhaust gas exhaust port provided at a position away from the combustion device, and at a position near the exhaust port, latent heat recovery is provided. The air gas for the air curtain that has passed through the side of the arrangement area of the heat exchanger is guided to the side of the combustion gas that has passed through the arrangement area of the latent heat recovery heat exchanger. The combustion apparatus according to claim 1, further comprising an air rectifier that guides the air to the exhaust pipe in a manner of enclosing the air with air for the air curtain. .   The combustion apparatus according to claim 6, wherein CO detection means for detecting carbon monoxide in the combustion gas is provided downstream of the air rectification unit in the flow of the combustion gas.

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