JP2000205658A - Combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a decrease in a thermal efficiency of a heat exchanger for recovering a latent heat. SOLUTION: A drain receiver 16 for receiving water droplets (drain) dropped from a heat exchanger 13 is arranged under the exchanger 13 for recovering a latent heat. The receiver 16 includes a plurality of plate members 36a, 36b in a multiple structure obtained by superposing them through an air layer 37. The receiver 16 is formed in the multiple structure to transfer the heat of exhaust gas flowing along a bottom of the receiver 16 to an upper surface of the receiver 16 to prevent the heat from being absorbed to the droplet of the upper surface. As a result, the heat of the gas is absorbed to the droplet on the receiver 16 before flowing to the exchanger 13 for recovering the latent heat, thereby preventing a problem of lowering the thermal efficiency of the exchanger 13 for recovering the latent heat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus such as a water heater of a type provided with a first heat exchanger and a second heat exchanger.

[0002]

2. Description of the Related Art FIG. 4 is a model diagram showing an example of a high-efficiency heat-exchange type combustion device which is being developed by the applicant and is under development. The combustion device (apparatus) is a water heater, and as shown in the figure, a combustion chamber 2 is provided in an appliance case 1, and a burner 3 is provided in the combustion chamber 2.

A gas supply passage 4 for introducing fuel gas to the burner 3 is provided. The gas supply passage 4 includes on-off valves 5 and 6 for opening and closing the passage, and a gas amount supplied to the burner 3 by a valve opening degree. A proportional valve 7 to be controlled by the control is interposed. Fuel gas guided from the fuel gas supply source through the gas supply passage 4 is supplied to the burner 3 via the gas nozzle holder 8, and the burner 3 burns the supplied fuel gas.

A main heat exchanger 12, which is a first heat exchanger, is provided above the burner 3, and a second heat exchanger is provided above the main heat exchanger 12 (exhaust side). The latent heat recovery heat exchanger 13 is disposed at intervals. A water supply passage 14 for guiding water from a water supply source is connected to an inlet of the latent heat recovery heat exchanger 13, and an outlet of the latent heat recovery heat exchanger 13 is connected to the main heat exchanger via a pipe 9. 1
2 is connected to the input side. One end of a hot water supply passage 15 is connected to the outlet side of the main heat exchanger 12, and the other end of the hot water supply passage 15 is led to a hot water supply place such as a kitchen or a shower.

A combustion fan 10 for supplying and exhausting burner combustion is provided. Above the combustion chamber 2, exhaust gas generated by combustion of the burner 3 is guided to an exhaust outlet of a combustion device and discharged to the outside. The exhaust passage 11 communicates.
The combustion chamber 2 and the exhaust passage 11 constitute a ventilation passage for guiding exhaust gas generated by the combustion of the burner 3 through the main heat exchanger 12 and the latent heat recovery heat exchanger 13 to an exhaust outlet of the combustion equipment in order. ing.

As described above, in this apparatus, since the latent heat recovery heat exchanger 13 is further provided on the exhaust side of the main heat exchanger 12, most of the heat generated by the combustion of the burners 3 is supplied to the main heat exchanger 12. 12 (for example, burner 3
80% of the heat generated by the main heat exchanger 1
2), and most of the remaining heat is absorbed by the latent heat recovery heat exchanger 13. About 90% or more of the heat generated by the burner 3 is passed through the heat exchanger. It has a configuration that achieves high-efficiency heat exchange in which water can absorb heat. The latent heat recovery heat exchanger 13 absorbs not only the latent heat of the heat generated by the burner 3 but also the sensible heat that has not been completely absorbed by the main heat exchanger 12.

Since the water supplied from the water supply passage 14 enters the latent heat recovery heat exchanger 13, the surface temperature of the water pipe of the latent heat recovery heat exchanger 13 is low. The water vapor component in the gas adheres to the surface of the water tube of the latent heat recovery heat exchanger 13 due to the condensation phenomenon. Thus, due to the condensation phenomenon, the latent heat recovery heat exchanger 13
The amount of water droplets (drain) adhering to the surface increases with the passage of time. When the gravity applied to the drain becomes larger than the surface tension of the drain, the drain is discharged from the latent heat recovery heat exchanger 1.
Add dropwise from 3. A drain receiving portion 16 which is a water droplet receiving plate member for receiving the dropped drain is provided in a region between the main heat exchanger 12 and the latent heat recovery heat exchanger 13.

As described above, since the drain receiving portion 16 is provided in the region between the main heat exchanger 12 and the latent heat recovery heat exchanger 13, the exhaust gas passing through the main heat exchanger 12 is discharged from the drain receiving portion. After passing through the gap between the end of the drain receiving portion 16 and the inner wall surface of the combustion chamber 2 from below to above, the flow is changed to the horizontal direction to move the latent heat recovery heat exchanger 13 sideways. You will pass in the direction.

The drain received by the drain receiving portion 16 is configured to be discharged to the outside through a drain discharge passage 18, and the drain received by the drain receiving portion 16 is smoothly guided to the drain discharge passage 18. For this reason, the drain receiving portion 16 is inclined downward toward the drain discharge passage 18.

Further, since the drain attached to the latent heat recovery heat exchanger 13 is exposed to the exhaust gas, N
An acidic component such as Ox dissolves in the drain, and the acidic concentration of the drain is extremely high, for example, ph2 to 3. The drainage of such a high-acid drain as it is is a problem of environmental pollution. Is generated, the neutralization processing means 20 for neutralizing the drain is provided in the drain discharge passage 18.
The neutralized drain is discharged from the drain discharge passage 18 to the outside.

In the drawing, reference numeral 21 denotes an incoming water temperature sensor for detecting the temperature of water in the water supply passage 14, and 22 denotes a water amount sensor for detecting a flow rate of water flowing through the water supply passage 14.
Reference numeral 3 denotes a tap water temperature sensor that detects the tap water temperature supplied from the hot water supply passage 15.

The water heater is provided with a control device 25 for controlling a hot water supply operation, and a remote control 26 provided in a kitchen, a lavatory or the like is connected to the control device 25 by a signal. The remote controller 26 is provided with hot water supply temperature setting means for setting the hot water supply temperature.

The control device 25 controls the hot water supply operation, for example, as follows. When a hot water tap (not shown) provided at the distal end side of the hot water supply passage 15 is opened and the water flow sensor 22 detects the flow of water in the water supply passage 14, the on-off valves 5 and 6 are opened and the gas supply passage 4 The fuel gas is supplied to the burner 3 and the combustion fan 10 is rotated to drive the burner 3.
To start combustion of the burner 3.

The amount of combustion heat of the burner 3 is controlled so as to reach the hot water supply set temperature set in the remote controller 26, that is, the valve opening of the proportional valve 7 is controlled by the proportional valve drive current to the burner 3. Of the fuel gas supplied through the water supply passage 14 and then passed through the latent heat recovery heat exchanger 13 and the main heat exchanger 12 to be heated by the combustion heat of the burner 3 to produce hot water. Hot water supply passage 1
5 to the desired hot water supply location. Thereafter, when the hot water tap is closed and the stoppage of the water supply in the water supply passage 14 is detected by the water amount sensor 22, the on-off valve 6 is closed to stop the combustion of the burner 3, and the rotation of the combustion fan 10 is stopped. , Preparing for the next hot water supply operation.

[0015]

By the way, in the apparatus shown in FIG. 4, since the drain receiving portion 16 is formed by a single plate member such as stainless steel, the heat exchanger 13 for latent heat recovery is used. It has been found by the applicant's experiment that the thermal efficiency is reduced.

That is, when the drain dropped from the latent heat recovery heat exchanger 13 adheres to the upper surface of the drain receiving portion 16, the heat of the exhaust flowing on the bottom side of the drain receiving portion 16 is reduced by the drain receiving portion. The heat is absorbed by the drain through the drain 16, and as a result, the calorific value of the exhaust flowing into the latent heat recovery heat exchanger 13 is reduced. From this,
Inevitably, the amount of heat absorbed from the exhaust gas to the latent heat recovery heat exchanger 13 decreases, and the heat efficiency of the latent heat recovery heat exchanger 13 decreases.

Further, it has been found that the heat efficiency of the latent heat recovery heat exchanger 13 may be reduced for the following reasons. As shown in FIG. 6A, the latent heat recovery heat exchanger 13 is substantially horizontal to a direction from the exhaust inlet side of the heat exchanger 13 to the exhaust outlet side (along the exhaust passage). It has a plurality of straight water pipes 30 along the direction, these straight water pipes 30 are juxtaposed with a gap therebetween, and are further connected to each other through a U-shaped water pipe 31 to form one water passage. are doing.

Conventionally, the latent heat recovery heat exchanger 13 is formed by a parallel-pass type heat exchanger. That is,
As shown in FIG. 6B, for example, a straight water pipe 30a
And a group of linear water pipes 30b, a group of linear water pipes 30c and 30d, a group of linear water pipes 30e and 30f, and a plurality of linear water pipes 30 of the latent heat recovery heat exchanger 13. A group of water tubes arranged side by side with a gap therebetween in a direction perpendicular to the direction from the exhaust inlet side to the exhaust outlet side (vertical direction in the example shown in FIG. 6B) is referred to as a water tube juxtaposed group. In this case, in the parallel-pass type heat exchanger, each water pipe on one side of the adjacent water pipe side-by-side group is disposed at a position facing the water pipes of the other side water pipe side-by-side group.

As described above, since the latent heat recovery heat exchanger 13 is a parallel path type heat exchanger, for example, rainwater blows from the exhaust outlet of the combustion equipment to the latent heat recovery heat exchanger 13 together with the headwind. In this case, the rainwater easily passes from the exhaust outlet side of the latent heat recovery heat exchanger 13 to the exhaust inlet side of the latent heat recovery heat exchanger 13 through the space between the straight water pipes 30. Not only the straight water pipe 30 on the exhaust outlet side of the vessel 13 but also the straight water pipe 30 on the exhaust inlet side
There is also a risk that rainwater will adhere to the water. Since the rainwater adhering to the straight water pipe 30 absorbs the heat of the straight water pipe 30 and the heat of the exhaust and drops, as described above, from the exhaust outlet side of the latent heat recovery heat exchanger 13 to the exhaust inlet side. Hang each straight water pipe 30
If rainwater adheres to the heat exchanger, the thermal efficiency of the latent heat recovery heat exchanger 13 will be significantly reduced.

Further, the present applicant has noticed that the thermal efficiency of the latent heat recovery heat exchanger 13 may be reduced for the following reasons. As shown in FIG. 7A, for example, the latent heat recovery heat exchanger 13 includes a plurality of linear water pipes 30 and side plate members 33 (33a, 33b) supporting both ends of the linear water pipes 30. ) And fin plate 3
4 and the side plate member 33 and the drain receiving portion 16 are screwed.

That is, in the prior art, the straight water pipe 30 is inserted into each through hole of the side plate member 33 and the fin plate 34, and the U-shaped water pipe 31 is connected to the straight water pipe 30 so as to connect the latent heat recovery heat exchanger. After completing the manufacture of the drain 13, the drain receiver 16 and the side plate member 33 were screwed together to attach the drain receiver 16 below the latent heat recovery heat exchanger 13.

However, as described above, before the drain receiving portion 16 and the side plate members 33 (33a, 33b) are screwed, the interval between the side plate members 33a, 33b is determined, and the space between the latent heat recovery heat exchangers 13 is determined. Since the distance between the side plate members 33a and 33b varies, the drain receiving portion 16 and the side plate member 3
After the screw 3 is screwed, the drain receiving portion 16 may be bent as shown in FIG.

As described above, when the drain receiving portion 16 is bent, a gap 35 is formed between the bottom surface of the latent heat recovery heat exchanger 13 and the drain receiving portion 16, and a part of the exhaust gas is generated by the gap 3.
5, that is, the latent heat recovery heat exchanger 13
As a result, the exhaust gas that does not exchange heat is generated, and as a result, the thermal efficiency of the latent heat recovery heat exchanger 13 decreases.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a combustion apparatus capable of preventing a decrease in the thermal efficiency of a latent heat recovery heat exchanger as a second heat exchanger. Is to provide.

[0025]

Means for Solving the Problems To achieve the above object, the present invention has the following structure to solve the above problems. That is, the first invention provides a first heat exchanger that heats water using combustion heat of a burner, and a first heat exchanger that is disposed on the exhaust side of the first heat exchanger with an interval therebetween. A second heat exchanger, and a ventilation passage for guiding exhaust gas generated by burner combustion through the first heat exchanger and the second heat exchanger to an exhaust outlet of the combustion equipment is formed. In the combustion apparatus, a water drop receiving plate member for receiving water drops dropped from the second heat exchanger is provided in a region of the ventilation passage between the first heat exchanger and the second heat exchanger. The water droplet receiving plate member has a configuration in which a plurality of plate members have a multi-layered structure in which the plate members are stacked via one or more heat insulating layers.

A second aspect of the present invention is a means for solving the above-mentioned problem with a configuration in which the heat insulating layer constituting the first aspect of the present invention is formed by an air layer.

According to a third aspect of the present invention, there is provided the structure of the first or second aspect, wherein the second heat exchanger is a horizontal heat exchanger that is substantially perpendicular to a direction from an exhaust inlet side to an exhaust outlet side of the heat exchanger. A juxtaposition group of a plurality of straight water pipes along the direction is arranged in a direction along the ventilation passage with a gap therebetween, and at least between the respective water pipe juxtaposition groups, between each water pipe of the water pipe juxtaposition group. Means for solving the above-mentioned problem is a configuration in which a linear water pipe is arranged at a position substantially opposed to the water pipe.

According to a fourth aspect of the present invention, there is provided the first, second or third aspect.
The second heat exchanger has a configuration in which a plurality of linear water pipes are arranged side by side with a gap therebetween,
The two end portions of the water tubes are supported by side plate members, respectively, and both end portions of the water droplet receiving plate member are bent in the upright direction, and the upright portions constitute the side plate members. The combustion device according to claim 1 or claim 2 or claim 3.

According to a fifth aspect of the present invention, there is provided the first, second or third aspect.
Or, the exhaust gas passes through the first heat exchanger from the bottom to the top, and the exhaust gas passes through the water droplet receiving plate member and passes through the second heat exchanger.
And the water droplet receiving plate member is inclined downward in the direction from the exhaust inlet side to the exhaust outlet side of the second heat exchanger. The means for solving the above-mentioned problem has a configuration in which a water droplet collecting part for collecting water droplets received by the water droplet receiving plate member is provided on the exhaust outlet side.

In the invention having the above structure, for example, the water drop receiving plate member has a multiplex structure in which a plurality of plate members are stacked via one or more heat insulating layers. The heat insulating layer prevents the heat of the exhaust gas flowing along the bottom surface of the water droplet receiving plate member (that is, the exhaust gas before entering the second heat exchanger) from being transferred to the upper surface of the water droplet receiving plate member. The second on the upper surface of the water drop receiving plate member
Even if there is a water droplet dropped from the heat exchanger, the exhaust heat before entering the second heat exchanger is not absorbed by the water droplet, and the exhaust heat is absorbed by the water droplet on the water droplet receiving plate member. Thus, it is possible to prevent a decrease in the thermal efficiency of the second heat exchanger caused by being performed.

[0031]

Embodiments of the present invention will be described below with reference to the drawings.

The combustion apparatus of the first embodiment has substantially the same configuration as the high-efficiency heat exchange type combustion apparatus shown in FIG. 4, and is characterized in that, as shown in FIG. The drain receiving portion 16 which is a water drop receiving plate member has a multiple structure. In the description of the first embodiment, the same components as those of the combustion equipment shown in FIG. 4 are denoted by the same reference numerals, and redundant description of the common components will be omitted.

In the first embodiment, as shown in FIG. 1, the drain receiving portion 16 has a structure in which an upper plate member 36b is disposed above a bottom plate member 36a via an air layer 37. It has a heavy structure.

The plate members 36a and 36b are formed of a plate member having excellent heat resistance and corrosion resistance, such as stainless steel, and the air layer 37 transfers heat from the bottom plate member 36a to the upper plate member 36b. It functions as a heat insulating layer for preventing heating.

According to the first embodiment, since the drain receiving portion 16 has a double structure in which the two plate members 36 are stacked via the air layer 37, The heat of the exhaust gas flowing along the bottom plate member 36a of the drain receiving portion 16 can be prevented from being transferred from the bottom plate member 36a to the upper plate member 36b, thereby recovering the latent heat. To prevent the heat of exhaust gas flowing along the bottom plate member 36a from being absorbed by the drain when the drain dropped from the heat exchanger 13 is attached to the upper plate member 36b. Can be.

As described above, since the exhaust heat can be prevented from being absorbed by the drain before flowing into the latent heat recovery heat exchanger 13, the latent heat recovery heat exchanger 13 caused by the drain heat absorption can be prevented. Can be suppressed from decreasing in thermal efficiency.

Further, as in the conventional case, the drain receiving portion 16 is
When the drain on the drain receiving portion 16 is formed of a plurality of plate members and absorbs the heat of the exhaust gas flowing along the bottom surface of the drain receiving portion 16, the moisture of the drain evaporates due to the absorbed heat. The acid concentration of the drain increases, and the drain having the increased acid concentration causes the drain receiving portion 16
May corrode. In particular, when the degree of corrosion advances and a hole is formed in the drain receiving portion 16, there occurs a problem that the drain falls to the main heat exchanger 12 through the hole. A bad effect such as corrosion of the heat exchanger 12 occurs.

On the other hand, in the first embodiment, as described above, the drain receiving portion 16 has a double structure in which the plate member 36 is overlapped with the air layer 37 interposed therebetween. It is possible to prevent the drain on the drain receiving portion 16 from absorbing heat of exhaust flowing along the bottom surface of the drain receiving portion 16,
Thus, it is possible to prevent the acid concentration of the drain from increasing due to the evaporation of water, and to prevent the drain receiving portion 16 from being corroded.

Hereinafter, a second embodiment will be described. In the second embodiment, the straight water pipe 30 of the latent heat recovery heat exchanger 13 is arranged in a staggered arrangement as shown in FIG.
Are disposed, and the latent heat recovery heat exchanger 13 caused by rainwater entering from the exhaust outlet of the combustion equipment.
The structure for preventing the problem of the decrease in thermal efficiency is provided. The other configuration is the same as that of the first embodiment. The same components as those of the first embodiment are denoted by the same reference numerals, and the description of the common portions will not be repeated.

In the second embodiment, in the latent heat recovery heat exchanger 13, a plurality of straight water pipes 30 are vertically arranged as shown in FIG.
0C and 30D, and these water pipe juxtaposed groups are arranged along the ventilation passage. Between the water pipe juxtaposed groups, the straight water pipes 30 are located at positions opposing each water pipe of the water pipe juxtaposed group. Are arranged.

Specifically, in the example shown in FIG. 2, a straight water pipe 30 is provided between the water pipe side-by-side group 30A and the water pipe side-by-side group 30B.
a straight water pipe 30α is provided at a position opposed to a gap between the straight water pipe 30a and the straight water pipe 30b and a gap between the straight water pipe 30c and the straight water pipe 30d.
Between the straight water pipe 30c and the straight water pipe 30d, and between the straight water pipe 30e and the straight water pipe 30f, a straight water pipe 30β is provided at a position facing the gap between the straight water pipe 30e and the straight water pipe 30f. A water pipe side-by-side group 30C and a water pipe side-by-side group 3
0D, the gap between the straight water pipe 30e and the straight water pipe 30f, and the straight water pipe 30g and the straight water pipe 30f.
A straight water pipe 30γ is provided at a position opposed to the gap between h.

According to the second embodiment, the straight water pipes 3 are located at positions opposing each other between the straight water pipes 30 in the water pipe side-by-side group.
0, rainwater blown from the exhaust outlet of the combustion equipment passes through the gap between the straight water pipe 30a and the straight water pipe 30b on the exhaust outlet side of the latent heat recovery heat exchanger 13, and further heat exchange for latent heat recovery When trying to enter the exhaust inlet side (back side) of the vessel 13, the rainwater enters the straight water pipe 3.
0α will be almost blocked. In addition, even if there is rainwater that bypasses the straight water pipe 30α and enters further, the rainwater is prevented by the straight water pipe 30c or the straight water pipe 30d.

As described above, the entry of rainwater can be stopped at the exhaust outlet side of the latent heat recovery heat exchanger 13.
The rainwater does not enter the exhaust inlet side of the latent heat recovery heat exchanger 13, and the linear water pipe 30 that constitutes the latent heat recovery heat exchanger 13.
Since rainwater does not adhere to many of the heat exchangers, it is possible to avoid a problem of a decrease in the thermal efficiency of the latent heat recovery heat exchanger 13 caused by the rainwater.

Further, when the latent heat recovery heat exchanger 13 is formed by a parallel-pass type heat exchanger as shown in FIG. When rainwater is blown, the rainwater passes between the linear water pipes 30 of the latent heat recovery heat exchanger 13, and from the latent heat recovery heat exchanger 13 to the main heat exchanger 1 below the rainwater.
2 may have rainwater dripping. As described above, if rainwater is dropped on the main heat exchanger 12, adverse effects such as corrosion of the main heat exchanger 12 due to the rainwater may occur.

On the other hand, in the second embodiment, as described above, rainwater enters the latent heat recovery heat exchanger 1.
3, the rainwater does not pass through the latent heat recovery heat exchanger 13 and drops onto the main heat exchanger 12 as described above. The problem of rainwater falling onto the exchanger 12 can be reliably avoided.

Further, in the second embodiment, the straight water pipes 30 are arranged side by side in a staggered arrangement as shown in FIG. 2, so that the exhaust gas flowing into the latent heat recovery heat exchanger 13 is It flows while bypassing each of the linear water pipes 30, so that the surface area of the linear water pipe 30 with which the exhaust gas contacts can be increased, and the heat efficiency of the latent heat recovery heat exchanger 13 can be improved.

Hereinafter, a third embodiment will be described. FIG. 3A shows a characteristic part extracted from the third embodiment. In the third embodiment, the configuration of the combustion apparatus other than the portion shown in FIG. 3A is substantially the same as the configuration of each embodiment, and has the same name as the component shown in each embodiment. Portions are given the same reference numerals, and redundant description of common portions is omitted.

In the third embodiment, both end portions of a plate member such as stainless steel having excellent heat resistance and corrosion resistance are bent in the upright direction as shown in FIGS. 3A and 3B, respectively. The upright portion forms the side plate member 33 of the latent heat recovery heat exchanger 13, and the bottom portion forms the upper plate member 36 a of the drain receiving portion 16. Upper plate member 36
The plate member 36b on the bottom side is disposed under the space a through the gap to form the drain receiving portion 16.

A drain collecting section 38, which is a drain collecting section, is provided on the exhaust outlet side of the upper plate member 36a. In the third embodiment, the drain receiving portion 16 is arranged so as to be inclined downward from the exhaust inlet side to the exhaust outlet side. For this reason, the latent heat recovery heat exchanger 13 is provided. When the drain is dropped and received by the drain receiving portion 16 (upper plate member 36a), the drain flows along the upper surface of the upper plate member 36a to the exhaust outlet side. The drain collecting section 38 receives and collects the drain flowing to the exhaust outlet side.

In the third embodiment, the drain collecting portion 38 is independent of the upper plate member 36a, and is disposed below the exhaust outlet side of the latent heat recovery heat exchanger 13. I have. The drain collecting section 38 is provided in the state shown in FIG.
As shown in FIG. 1, the box body 40 is formed of, for example, resin, and the upper surface of the box body 40 is open. An opening 41 is formed on the bottom surface of the box 40, and the opening 41 is formed.
A cylindrical portion 42 protruding downward from is formed. Further, the box 40 is provided with a drain collecting portion 38 for the side plate member 33.
A mounting portion 43 for mounting the screw is formed, and the mounting portion 43 has a screw insertion hole 4 for inserting a screw.
4 are formed.

On the other hand, as shown in FIG. 3B, the exhaust outlet portion of the upper plate member 36a is bent downward to form a drain lead-out portion 45, and the side plate member 33 has the above drain. A screw insertion hole 46 for inserting a screw for attaching the collecting portion 38 is formed.

As shown in FIG. 3A, the drain lead-out part 45 is inserted into the box 40 of the drain collecting part 38, and the mounting part 43 of the drain collecting part 38 is connected to the side plate member 33 more than the side plate member 33. After adjusting the position of the screw insertion hole 44 of the drain collecting section 38 and the screw insertion hole 46 of the side plate member 33 to the outside, a screw is inserted through the screw insertion holes 44 and 46 to the side plate member 33. The drain collecting part 38 is screwed.

In the third embodiment, the latent heat recovery heat exchanger 13, the drain receiving section 16, and the drain collecting section 38
Are unitized, and after the unit is manufactured and completed, the unit will be mounted inside the combustion equipment, and at this time, as described above,
The drain receiving portion 16 is disposed so as to be inclined downward in a direction from the exhaust inlet side to the exhaust outlet side, and the cylindrical portion 42 of the drain collecting portion 38 is connected to the drain discharge passage 18. As described above, since the cylindrical portion 42 of the drain collecting portion 38 is connected to the drain discharge passage 18, the drain collected in the drain collecting portion 38 is discharged to the outside through the cylindrical portion 42 and the drain discharge passage 18. Will be done.

In the third embodiment, the linear water pipes 30 of the latent heat recovery heat exchanger 13 are arranged in a staggered arrangement as shown in the second embodiment. I have. For this reason, when rainwater blows into the exhaust outlet side of the latent heat recovery heat exchanger 13 from the exhaust outlet of the combustion equipment, most of the sprayed rainwater is, for example, a straight water pipe on the exhaust outlet side shown in FIG. The droplets are dropped downward when hitting 30a, 30b, 30α.

In the third embodiment, as described above, the drain collecting section 38 is disposed below the exhaust outlet side of the latent heat recovery heat exchanger 13, so that the latent heat recovery heat exchange In the third embodiment, the drain collecting section 38 is configured to collect the drain and the rainwater in the third embodiment. In the third embodiment, rainwater dropped from the latent heat recovery heat exchanger 13 is discharged to the outside from the drain collecting section 38 through the drain discharge passage 18 like the drain.

According to the third embodiment, both end portions of the upper plate member 36a of the drain receiving portion 16 are bent in the upright direction, and the upright portions are bent in the heat exchanger 1 for latent heat recovery.
3, the drain receiving portion 16
Can be prevented from bending.

That is, the side plate member 33 and the drain receiving portion 16
Are independent of each other, as described above, the drain receiving portion 16 is bent due to the screwing between the both end portions of the drain receiving portion 16 and the side plate member 33. Thus, when the drain receiving portion 16 is bent, the latent heat recovery heat exchanger 1
A gap is formed between the bottom side of the fuel cell 3 and the drain receiving portion 16, and a part of the exhaust gas passes through the gap, and the exhaust gas is discharged to the outside without being exchanged with the latent heat recovery heat exchanger 13. As a result, a problem arises in that the thermal efficiency of the latent heat recovery heat exchanger 13 is reduced.

On the other hand, in the third embodiment, both end portions of one plate member are bent in the upright direction, the upright portions are formed as side plate members 33, and the bottom portion is drain receiving. Since the drain receiving portion 16 is provided with the plate member 36a on the upper side of the portion 16, it is possible to prevent the drain receiving portion 16 from being bent, whereby the bottom side of the latent heat recovery heat exchanger 13 and the drain receiving portion It is possible to avoid a gap from being formed between the first and second portions 16. For this reason, all the exhaust gas that has passed through the main heat exchanger 12 passes through the latent heat recovery heat exchanger 13 and exchanges heat with the latent heat recovery heat exchanger 13. A decrease in thermal efficiency can be prevented.

In the related art, since the side plate member 33 and the drain receiving portion 16 are separate and independent, the operation of screwing the side plate member 33 and the drain receiving portion 16 in the manufacturing process of the combustion equipment is performed. Since it is necessary and the number of screwed portions is large, the work of screwing the side plate member 33 and the drain receiving portion 16 is troublesome and time-consuming, and the work efficiency is poor. On the other hand, in the configuration of the third embodiment, there is no need to screw the side plate member 33 and the drain receiving portion 16, and it is possible to improve the working efficiency of manufacturing the combustion equipment.

Further, in the third embodiment, a drain collecting part 38 is provided on the exhaust outlet side of the drain receiving part 16, and the drain collecting part 38 is attached to the side plate member 33 so that the drain receiving part 16 By arranging the drain collecting section 38 inside the combustion device after the arrangement on the exhaust outlet side, the operation of assembling the drain collecting section 38 inside the combustion device becomes simple, and the assembling work efficiency of the combustion device can be improved.

Further, when the drain receiving portion 16 and the side plate member 33 are separate and independent as in the prior art, a slight gap is easily generated at the connection portion between the drain receiving portion 16 and the side plate member 33, and the gap is easily formed. If the drain has entered, there is a possibility that a problem occurs in that the connection portion between the drain receiving portion 16 and the side plate member 33 is corroded. On the other hand, in the third embodiment, the drain receiving portion 16 and the side plate member 3
Since there is no gap between the three, the problem caused by the gap between the connection portion between the drain receiving portion 16 and the side plate member 33 can be prevented.

It should be noted that the present invention is not limited to the above embodiments, and various embodiments can be adopted. For example, in each of the above embodiments, the air layer 37 is provided between the upper plate member 36a and the bottom plate member 36b of the drain receiving portion 16, but instead of the air layer 37, a heat insulating layer is provided. A heat insulating layer made of a material may be provided. Also in this case, the effect as described in the first embodiment, that is, the heat of the exhaust gas is prevented from being absorbed by the drain on the drain receiving portion 16 and the heat efficiency of the latent heat recovery heat exchanger 13 is reduced. The effect that the drop can be prevented and the effect that the drain receiving portion 16 is corroded due to the increase in the acid concentration of the drain on the drain receiving portion 16 due to the drain heat absorption can be prevented. Obtainable.

The upper plate member 3 of the drain receiving portion 16
Two heat insulating layers of an air layer and a heat insulating layer made of a heat insulating material may be interposed between 6a and the bottom plate member 36b,
A plurality of heat insulating layers made of different heat insulating materials
A layer or more may be provided between the plate members 36a and 36b.

Further, in each of the above embodiments, the drain receiving portion 16 has a double structure in which the upper plate member 36a and the bottom plate member 36b are overlapped with the air layer 37 interposed therebetween.
The drain receiving portion 16 may have a triple or more multiplex structure.
Also in this case, of course, an air space or a heat insulating material is interposed between the respective plate members constituting the drain receiving portion 16.

Further, in the second and third embodiments, the number of the linear water tubes 30 of the latent heat recovery heat exchanger 13 is eleven, but the number of the linear water tubes 30 is not limited to the number. In the present invention, the number of straight water pipes is 10 or less or 1
The present invention can be applied to a combustion device having two or more latent heat recovery heat exchangers.

Furthermore, in the third embodiment, the straight water pipes 30 of the latent heat recovery heat exchanger 13 are arranged in a staggered arrangement as shown in the second embodiment. However, for example, a means such as a rain return for preventing rainwater blown from the exhaust outlet of the combustion equipment to reach the latent heat recovery heat exchanger 13 is provided, and the rainwater enters the latent heat recovery heat exchanger 13. When this can be substantially avoided, there is almost no fear that rainwater blows onto the latent heat recovery heat exchanger 13, so the straight water pipe 30 may be arranged in a parallel path type as shown in FIG. .

Further, as an application example of the present invention, for example, in a high-efficiency heat exchange type combustion apparatus having a configuration in which the drain receiving portion 16 is formed of one plate member as in the conventional example, the second embodiment is described. As shown in the example, the linear water tubes 30 of the latent heat recovery heat exchanger 13 may be arranged in a staggered arrangement. In this case, it is possible to prevent a decrease in the thermal efficiency of the latent heat recovery heat exchanger 13 caused by rainwater.

Further, as an application example of the present invention, for example, the drain receiving portion 16 has a structure composed of one plate member as in the conventional example, and the latent heat recovery heat exchanger 13 has a parallel path type shown in FIG. In a high-efficiency heat-exchange type combustion device constituted by a heat exchanger, both end portions of the drain receiving portion 16 are bent in the upright direction, and the upstanding portion forms the side plate member 33 of the latent heat recovery heat exchanger 13. It may be configured. In this case, the bending of the drain receiving portion 16 can be prevented, and a decrease in the thermal efficiency of the latent heat recovery heat exchanger 13 due to the bending of the drain receiving portion 16 can be prevented.

Further, in each of the above embodiments, the burner 3
Is a burner of a type in which a combustion surface is formed on the upper side. For example, as an application example of the present invention, a burner of an inverted combustion type in which a combustion surface is formed on the lower side of a burner 3 as shown in FIG. 3 may be provided with the following configuration.

Each component of the combustion equipment shown in FIG. 5 is denoted by the same reference numeral for the same component as each component of the combustion equipment shown in each of the above embodiments. That is, in the combustion apparatus shown in FIG. 5, the burner 2 of the upside-down combustion type is provided.
A main heat exchanger 12 is provided, and a combustion fan 10 for supplying and exhausting burner combustion is provided above the burner 3. Further, an exhaust passage 11 for guiding exhaust gas generated by combustion of the burner 3 to the outside is provided. The exhaust passage 9 has a configuration in which the downward flow of exhaust gas passing through the main heat exchanger 3 is laterally converted, and the exhaust gas flow is upwardly converted and guided to the exhaust outlet of the combustion equipment.

The latent heat recovery heat exchanger 4 is disposed in the exhaust passage 9, and the inner wall portion of the exhaust passage disposed below the latent heat recovery heat exchanger 4 functions as the drain receiving portion 12. . An opening 23 is provided in an inner wall portion of the exhaust passage functioning as the drain receiving portion 12. A drain tank 50 is disposed below the opening 48, and a drain discharge passage 18 is connected to the drain tank 50. The drain dropped from the latent heat recovery heat exchanger 4 is supplied to the drain receiving portion. 12 and the drain receiving portion 1
2 to the drain tank 50, and is discharged from the drain tank 50 to the outside through the drain discharge passage 18.

In the above-described combustion apparatus of the upside-down combustion type,
As shown in FIG. 5, the main heat exchanger 12 and the latent heat recovery heat exchanger 13 may be provided side by side. In such a case, the main heat exchanger 12 and the latent heat recovery heat exchanger 13 are provided. 13 may be provided with a partition plate member 51 in an area sandwiched between the two. In such a case, even if the partition plate member 51 is formed by a multi-layer plate member in which a plurality of plate members as shown in the above embodiments are stacked via one or more heat insulating layers. Good.

Further, in each of the above embodiments, a water heater for burning fuel gas has been described as an example. However, in the present invention, a heat exchanger for performing steam generating steam and providing a latent heat recovery heat exchanger is provided. Any combustion equipment can be applied. For example, a hot-water supply bath complex with a latent heat recovery heat exchanger with a bath function added to the hot water supply function, a bath device with a latent heat recovery heat exchanger with only the bath function, and a heating unit with a latent heat recovery heat exchanger Combustion equipment such as a hot water supply / heating unit equipped with a heat exchanger for latent heat recovery, a water heater / bath water combination unit using a fuel other than gas, such as oil, or a single-function bath / heater, etc. Can also be applied.

[0074]

According to the present invention, since the water drop receiving plate member has a multi-layer structure in which a plurality of plate members are stacked via one or more heat insulating layers, the water drop receiving plate member extends along the bottom surface of the water drop receiving plate member. The heat of the exhaust gas flowing through the water droplet receiving plate member can be prevented from being absorbed by the water droplets on the water droplet receiving plate member via the water droplet receiving plate member, and the heat efficiency of the second heat exchanger caused by the water droplet heat absorption can be prevented. be able to.

In the case where the heat insulating layer is formed by an air layer, the water drop receiving plate member has a structure in which a plurality of plate members are stacked with a gap therebetween, and therefore, a heat insulating layer is provided between the plurality of plate members. The structure of the water drop receiving plate member can be simplified as compared with the case where a material is interposed.

In the second heat exchanger, a group of a plurality of water pipes arranged in a line in a horizontal direction substantially perpendicular to the direction from the exhaust inlet side to the exhaust outlet side of the heat exchanger is provided with a gap therebetween. The water pipes are disposed in a direction along the ventilation passage, and at least a space between the water pipes is provided with a straight water pipe at a position substantially opposed to each water pipe in the water pipes. In the case where rainwater enters from the exhaust outlet of the combustion equipment to the second heat exchanger, the rainwater is collected by a group of water pipes arranged on the exhaust outlet side of the second heat exchanger. Of the second heat exchanger, and falls into the exhaust inlet side of the second heat exchanger with respect to the water pipes disposed at positions substantially facing each other between the water pipes or the water pipes in the group of water pipes. To prevent rainwater from adhering to the water pipe on the exhaust inlet side of the second heat exchanger. Can. As a result, it is possible to prevent a decrease in the thermal efficiency of the second heat exchanger caused by rainwater adhesion.

In the case where both end portions of the water drop receiving plate member are bent in the rising direction and the rising portions are formed as side plate members, the water drop plate member is bent to be in contact with the bottom side of the second heat exchanger. A gap can be prevented from being formed between the water droplet plate member. When a gap is formed between the bottom side of the second heat exchanger and the water droplet receiving plate member, part of the exhaust gas passes through the gap without passing through the second heat exchanger, that is, the second heat exchange. It is discharged to the outside without exchanging heat with the heat exchanger, which causes a problem that the heat efficiency of the second heat exchanger is reduced. On the other hand, as described above, the second heat exchanger is configured to prevent the water droplet plate member from bending and forming a gap between the bottom side of the second heat exchanger and the water droplet plate member. Problems caused by the gap between the bottom side of the exchanger and the water drop receiving plate member can be avoided.

In the case where the water droplet collecting portion is provided on the exhaust outlet side of the water droplet receiving plate member, the water droplet collecting portion is attached to the water droplet receiving plate member, and then the water droplet collecting portion is attached to the inside of the combustion equipment, so that the water droplet collecting portion is provided. The work of attaching the collecting part can be easily performed, and the efficiency of the assembling work of the combustion equipment can be improved.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram extracting and showing characteristic components in the first embodiment.

FIG. 2 is an explanatory diagram extracting and showing characteristic components in the second embodiment.

FIG. 3 is an explanatory diagram extracting and showing characteristic components in the third embodiment.

FIG. 4 is a model diagram showing an example of a combustion apparatus provided with a heat exchanger for latent heat recovery.

FIG. 5 is a model diagram showing an example of an upside-down combustion type combustion device with a latent heat recovery heat exchanger.

FIG. 6 is an explanatory diagram showing a problem that occurs when the latent heat recovery heat exchanger is a parallel-pass type heat exchanger.

FIG. 7 is an explanatory view showing a problem that occurs when the water droplet receiving plate member and the side plate member of the latent heat recovery heat exchanger are separate and independent.

[Explanation of symbols]

 Reference Signs List 3 burner 11 exhaust passage 12 main heat exchanger 13 latent heat recovery heat exchanger 16 drain receiving plate member 30 linear water pipe 31 U-shaped water pipe 33 side plate member 36 plate member 37 air layer 38 drain collecting part

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[Procedure amendment]

[Submission date] January 28, 1999 (1999.1.2
8)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

FIG. 2

FIG. 3

FIG. 4

FIG. 5

FIG. 6

FIG. 7

Claims (5)

[Claims] 1. A first heat exchanger for heating water using combustion heat of a burner, and a second heat exchanger disposed on the exhaust side of the first heat exchanger with an interval therebetween. An exhaust generated by the burner combustion.
And a ventilation passage leading to the exhaust outlet of the combustion equipment through the heat exchanger in turn, and a second passage in a region of the ventilation passage between the first heat exchanger and the second heat exchanger. In a combustion apparatus provided with a water drop receiving plate member for receiving water drops dropped from a heat exchanger, the water drop receiving plate member has a multi-layered structure in which a plurality of plate members are stacked via one or more heat insulating layers. Combustion equipment characterized by the fact that: 2. The combustion apparatus according to claim 1, wherein the heat insulating layer is formed by an air layer. 3. A second heat exchanger, wherein a group of a plurality of linear water tubes arranged in a horizontal direction substantially perpendicular to a direction from an exhaust inlet side to an exhaust outlet side of the heat exchanger is spaced from each other. A configuration in which a straight water pipe is disposed at a position substantially opposed to each water pipe in the water pipe side-by-side group at least between the respective water pipe side-by-side groups. The combustion device according to claim 1 or 2, wherein: 4. The second heat exchanger has a configuration in which a plurality of linear water pipes are arranged side by side with a gap therebetween, and both ends of the water pipes are supported by side plate members, respectively. 4. The combustion apparatus according to claim 1, wherein both end portions of the receiving plate member are bent in the upright direction, and the upstanding portions constitute the side plate members. 5. The exhaust gas passes through the first heat exchanger from bottom to top, and then passes laterally through the second heat exchanger with the water drop receiving plate member circumventing the water drop receiving plate member. The second heat exchanger is inclined downward in the direction from the exhaust inlet side to the exhaust outlet side, and has a water drop collecting part on the exhaust outlet side of the water drop receiving plate member for collecting water drops received by the water drop receiving plate member. The combustion device according to claim 1, claim 2, claim 3, or claim 4, wherein: