JPH06281130A - Forced air supply and exhaust type combustion device - Google Patents

Abstract

PURPOSE:To provide a forced air supply and exhaust type combustion device of which the structure is made smaller by drastically simplifying an introducing passage of the outside air to a fan, and at the same time, which can perform a combustion always with an appropriate air quantity. CONSTITUTION:A forced air supply and exhaust type combustion device has 2 units of fans 5, 6 and two burners 3, 4, and air is fed to each burner by the fan. The two fans are arranged in such a manner that air inlets 13, 14 of the fans 5, 61 may be confronted to each other, and the two air inlets are connected to a case 15 for air feed which is set between the fans, and the case for air feed communicates with the outside by a duct 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forced supply / exhaust type combustion device generally called an FF type combustion device, and a device having two or more fans, and particularly to a combustion used in a hot water supply device for a bath. It is a preferable device as a device.

[0002]

2. Description of the Related Art As a hot water supply device for a bath or the like, a forced supply / exhaust type combustion device for forcibly supplying / exhausting air to / from a burner with a fan is often used due to a demand for a small size and a large capacity. . Furthermore, in hot water supply devices such as baths,
Since it is necessary to selectively use one for additional boiling and one for hot water supply, there are many things that have two or more heat exchanger circuits at the same time, and the combustion device used for this has two or more burners, and this burner always has suitable air. A fan is provided for each burner to supply the.

FIG. 6 shows a forced air supply / exhaust type combustion apparatus used in a conventional bath water heater. In the conventional forced air supply / exhaust type combustion device, a large capacity burner 101 and a small capacity burner 102 are arranged in parallel, and a large capacity fan 103 and a small capacity fan 104 are connected to these burners, respectively. .

In the conventional forced air supply / exhaust type combustion apparatus, the fans 103 and 104 are arranged in parallel in the same direction as shown in FIG. That is, the suction port 1 of the fans 103 and 104
05 and 106 were arranged so as to open in the same direction. The suction ports 105 and 106 are respectively provided in the air supply case 1 branched from the upper collecting duct 109.
The air that is connected to the air intake ports 107 and 108 and is taken in from the air supply port 110 is guided to the air supply cases 107 and 108 via the air supply duct 111, and the suction ports 105 and 10 of the fan are connected.
It was introduced in 6.

[0005]

By the way, there is a strong demand for downsizing of water heaters due to deterioration of housing conditions in recent years.
For this reason, the conventional forced air supply / exhaust type combustion device has been required to be improved in order to be further downsized. Further, the conventional forced air supply / exhaust combustion device has a problem that the arrangement of the air supply duct is complicated and the assembly is difficult.

Further, in the conventional forced air supply / exhaust type combustion apparatus, since the air is supplied to the fan from the air supply case branched from the upper collecting duct, the pressure loss at the branch portion is large, and It was difficult to supply sufficient air to all the fans because the routes of air supply to the fans were different and the pressure loss was different for each fan.

In addition, in the case of a water heater, not all burners are always ignited, but each burner is repeatedly ignited and extinguished by hot water supply, showering, additional boiling, or the like. At this time, each fan is repeatedly operated and stopped according to the burner. However, when air is supplied to a fan via a complicatedly branched air supply path as in the conventional forced air supply / exhaust combustion device, the air pressure at the branch part changes locally due to the operation or stop of one fan. However, the pressure loss in the air supply path supplied to the other fan fluctuates significantly,
There was a defect that the air to be supplied was insufficient or excessive air was supplied too much.

Therefore, the present invention pays attention to such drawbacks of the prior art, and greatly simplifies the introduction path of the outside air to the fan, thereby making it possible to downsize the device and always burning with an appropriate amount of air. It is an object of the present invention to provide a forced air supply / exhaust type combustion device which can be operated.

[0009]

A feature of the present invention for achieving the above object is to provide a forced supply / exhaust type combustion apparatus having two or more fans, and the burners are supplied with air by the fans. The fan is arranged in a forced supply / exhaust type combustion apparatus in which the suction ports are arranged so as to face each other, and the suction ports are connected to a common air supply case communicating with the outside air (claim 1).

[0010]

According to the first aspect of the present invention, two or more fans, which are conventionally arranged in the same direction, are arranged so as to face each other, the suction ports are opposed to each other, and the air supply case is provided therebetween, so that a plurality of fans are provided. In contrast, you can supply air with only one case for air supply. Further, according to the present invention, air is distributed to the fan in the air supply case, and the air supply path on the way does not have a branched portion as in the conventional case. Therefore, the air supply path is simple, and it is not necessary to extend the duct inside the box of the water heater as in the conventional case. Further, since the air supply path has few curved paths and is linear, the pressure loss in the air supply path is small, and a duct thinner than the conventional one can be used to supply the same air as the conventional one.

Further, according to the present invention, in addition to the air supply path having few curved paths and smooth air flow, since the distances of the air supply paths of the plurality of fans are equal, the pressure loss is also equal, and all burners are even. Burns well. The air supply path to the air supply case is common to all fans and there is no branching part, so there is no local change in pressure, which has been a problem in the past, and the suction pressure of the other fan due to the operation or stop of one fan. Change is small.

It is desirable that the volume of the air supply case and the cross-sectional area of the duct to the air supply case are sufficiently large. When these are small, the influence of the air flow due to the suction of another fan causes As described in No. 5, turbulent flow or vortex is generated around each other's suction ports in the air supply case, and the suction capacity of each fan is reduced, so that sufficient air may not be supplied to the burner. In that case, insert a suitable partition plate in the air supply case to block the flow of air from the other fan and suppress the generation of turbulence and smooth the air flow to each fan. (Claim 2)

[0013]

EXAMPLES The present invention will be described in detail below with reference to specific examples in which the present invention is applied to a hot water supply device for a bath. FIG. 1 is a front sectional view of a hot water supply apparatus incorporating a forced supply / exhaust type combustion apparatus in a specific embodiment of the present invention. FIG. 2 is a side sectional view of the water heater of FIG. FIG. 3 is an enlarged view of the fan and the air supply case portion of FIG. FIG. 4 is a partial sectional view of a modified embodiment of the present invention.

In FIGS. 1 and 2, reference numeral 1 denotes a hot water supply apparatus incorporating a forced supply / exhaust type combustion apparatus in a specific embodiment of the present invention. The hot water supply apparatus 1 of the present embodiment has a box 2 in which two burners, a large capacity burner 3 and a small capacity burner 4, are installed. Both of the two burners are known fuel variable oil burners, and a nozzle 9 and an igniter 10 are provided in a cylindrical tube 8 inserted from the front of the combustion chamber 7.
Is inserted, and the nozzle 9 is arranged so as to face the lower combustion section 12 of the heat exchanger 11 installed in the combustion chamber 7. Fans 5 and 6 are directly connected to the cylindrical tubes 8 of the burners 3 and 4, respectively. The capacities of the fan 5 and the fan 6 are large and the fan 6 is small according to the capacity of the burner.

It should be noted that the suction port (bellmouth) 1 for the large capacity fan 5 and the small capacity fan 6 is particularly important here.
3 and 14 are in so-called different positions, and the two fans are arranged such that the suction ports face each other and the suction ports have almost the same height. The suction ports 13 and 14 of the fan are connected to a common air supply case 15. The air supply case 15 is a rectangular box made of a thin sheet of galvanized iron or tin plate. Two opposite side surfaces are opened, a round hole 16 with a flange is provided in the center of the upper surface, and a partition is provided inside. A plate 17 is provided. Partition board 17
Is vertically provided from below in the air supply case, slightly to one side from the center, and has a height substantially equal to the height of the suction ports 13 and 14 of the fan. The air supply case 15 is installed between the suction ports 13 and 14 of the fan, and the suction ports 13 and 14 of the fan 6 are inserted into the side openings so that the air supply case 15 and the fans 5 and 6 are It is connected.

A duct 18 extending vertically upward is connected to the round hole 16 in the upper portion of the air supply case 15. The duct 18 is further connected to an air supply port 19 provided right above the air supply case 15 to communicate with the outside of the box 2.

Now, when the burners 3 and 4 are ignited and the fans 5 and 6 rotate, air is supplied from the outside of the water heater 1 to the air supply port 1.
9, it is sucked into the duct 9, passes through the duct 18, and then the air supply case 15
to go into. The air supply path during this period is linear, and since there are no branches or curved paths, the pressure loss of the air supply is extremely small. In the air supply case 15, the air is rectified by the partition plate 17 and smoothly drawn into the suction ports 13 and 14 of the fans 5 and 6 as shown by the arrow in FIG. And fans 5, 6
The air that has come out is supplied to the combustion section 12 (the other side is not shown) via the burners 3 and 4.

In this embodiment, a partition plate 17 is provided inside the air supply case 15. This is the air supply case 15
In addition, it is a preferable configuration because the supplied air is rectified by the partition plate 17 to prevent the generation of turbulence or vortex inside the air supply case 15 and reduce the loss due to the suction resistance of the fan. . However, the volume of the air supply case 15 is allowed to be sufficiently large, and the air supply case 15 is
If it is possible to sufficiently absorb the generation of turbulent flow inside, this partition plate is not always necessary. Similarly, even when the duct 18 can have a sufficiently large cross-sectional area and the flow velocity of the air blown into the air supply case 15 is low, the partition plate is not necessary.

When the partition plate is provided, the design of the position where the partition plate is provided should be changed in a timely manner in consideration of the capacities of a plurality of fans, the wind speed around the suction port, or the operating frequency.
In this embodiment, since the capacity of the fan 5 is larger than the capacity of the fan 6, the partition plate is installed near the fan 5 so that more air is supplied to the fan 6.
Of course, as shown in FIG. 4, fans 41 and 42 of the same size
The partition plate 43 should be provided at the center of the air supply case 44 when the same is used at the same rotation speed. In this embodiment, the partition plate is provided vertically from below, but it may be provided from the side surface or in a slightly oblique direction depending on the connecting position of the duct and the like.

In the present embodiment, the shape of the air supply case 15 is a rectangular one because it is easy to machine. However, the present invention is not limited to this, and a normal cylindrical cylinder is used. You can use other things. It is also possible that the air supply case is not formed separately from the duct, the cross-sectional area of the duct is relatively large, and a part of the duct serves as the air supply case.

The number of fans is usually two, and it is rare that the number of fans is three or more, but it is also possible to have a configuration of three or more. In this case, the three fans are arranged radially, or only the two fans are opposed to each other.

Since the forced air supply / exhaust type combustion apparatus of the present invention is most suitable for use in a water heater for a bath, the above embodiment also relied on a water heater for a bath. It can also be used in devices other than water heaters and water heaters.

[0023]

In the forced air supply / exhaust type combustion apparatus of the present invention, the fans are arranged so that their suction ports face each other, and a common air supply case is connected to the suction ports. What was necessary for the air supply case, can supply air to multiple fans with only one air supply case, and it is possible to downsize the device by reducing the number of air supply cases There is.

Further, in the forced air supply / exhaust type combustion apparatus of the present invention, since it is not necessary to draw a duct inside the apparatus, the apparatus can be downsized by eliminating an extra space, and the air supply path is linear. Since the pressure loss is reduced, air can be supplied through a narrower duct than before, and the size of the device can be further reduced.

Furthermore, since the air supply path is linear and the pressure loss is reduced, sufficient air can be supplied to the burner, and the burner can be burned in a good oxygen state. In addition, since the plurality of burners have a common air supply path and there is no branched portion, there is an effect that a good combustion state can always be maintained regardless of the combination of the plurality of burners.

In addition, since the number of air supply cases is reduced and the ducts are thin and short, it is possible to reduce the amount of raw materials, and a space is created, so that there is an effect that assembly is facilitated.

The invention according to claim 2 has an effect of preventing the generation of turbulent flow and vortex in the air supply case and reducing the suction loss of the fan.

[Brief description of drawings]

FIG. 1 is a front sectional view of a hot water supply apparatus incorporating a forced air supply / exhaust type combustion apparatus in a specific embodiment of the present invention.

FIG. 2 is a side sectional view of the water heater of FIG.

FIG. 3 is an enlarged view of a fan and an air supply case portion of FIG. 1.

FIG. 4 is a partial cross-sectional view of a modified embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view of a fan and an air supply case showing an air flow in the air supply case when the air supply case has no partition plate.

FIG. 6 is a front sectional view of a forced air supply / exhaust combustion device used in a conventional bath water heater.

[Explanation of symbols]

 1 Hot Water Supply Device 2 Box 3 Burner 4 Burner 5 Fan 6 Fan 11 Heat Exchanger 15 Air Supply Case 17 Partition Plate 41 Fan 42 Fan 43 Partition Plate 44 Air Supply Case

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koji Kashihara 32 Akashi-cho, Chuo-ku, Kobe, Hyogo Stock company Noritsu (72) Inventor Hideya Nagao 32 Akashi-cho, Chuo-ku, Kobe, Hyogo Stock company In Noritz

Claims (2)

[Claims] 1. A forced air supply / exhaust type combustion apparatus having two or more fans, wherein burners are supplied to the burner by the fans, wherein the fans are arranged such that their suction ports face each other.
The forced air supply / exhaust combustion device, wherein the suction port is connected to a common air supply case communicating with the outside air. 2. The forced air supply / exhaust type combustion apparatus according to claim 1, wherein a partition plate is provided inside the air supply case.