JP2908974B2 - Liquid fuel combustion device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus using petroleum as a fuel, and more particularly to a household water heater and a heater.

[0002]

2. Description of the Related Art A conventional combustion apparatus of this kind is disclosed in
No. -14623. This will be described with reference to FIG.

In FIG. 2, reference numeral 31 denotes atomizing means using a pressure spray nozzle or the like for spraying liquid fuel at high pressure, and is connected to a fuel supply pump 32 by a fuel supply pipe 33. The fuel supply pump 32 is connected to a fuel tank (not shown) via a constant oil level device 34. Reference numeral 35 denotes a combustion air passage provided around the atomizing means 31 and is connected to a blowing means (not shown) using a blowing fan or the like.

Reference numeral 36 denotes a cylindrical mixing chamber, which has a curved side wall 3.
7 is provided with an opening 38 of an air passage 35 so as to face the mixing chamber 36.
Is also provided so as to face the inside of the mixing chamber 36. The lower portion of the mixing chamber 36 is an inclined bottom 39, and a fuel return pipe 47 is provided at the lowermost end. One end of the fuel return pipe 47 is connected to the constant oil level device 34.

[0005] At the upper part of the conveying passage 42, there is provided a mixing passage 44 which is configured to gradually expand upward and a porous flame opening 45 provided in the middle of the mixing passage 44. .

Reference numeral 54 denotes a flow rate measuring means provided in the middle of the fuel return pipe 47, and its signal line 55 is connected to a controller 58. A signal line 57 is connected from the controller 58 to the fuel supply pump 32. Then, the controller 58 receives the signal from the flow rate measuring means 54, and
2 is controlled to adjust the combustion amount by correcting the supplied fuel amount. 51 is an air flow, 49 is atomized fuel particles, and 50 is a flame.

In the above configuration, the fuel pressurized by the fuel supply pump 32 becomes fuel particles 49 atomized by the atomizing means 31 via the fuel supply pipe 33 and is ejected to the mixing chamber 36 to be mixed with air from the air passage 35. Mixed. The fuel particles having a large particle diameter adhere to or fall on the wall surface, and only the fuel particles having a small particle diameter are mixed with the air flow and burn at the flame opening 45 through the transport passage 42.

The large fuel particles that have adhered or fallen to the wall surface are collected from the bottom 39 through the fuel return pipe 47 to the constant oil level device 34. At this time, the return amount is measured by the flow rate measuring means 54, and the data is used to control the fuel supply pump 32 via the controller 58, so as to always obtain an appropriate and stable combustion amount.

[0009]

However, the above conventional configuration has the following problems.

The change of the return amount measured by the flow rate measuring means 54 is minute, and the flow rate measuring means 54 becomes expensive.

If the controller 58 attempts to finely control the fuel supply pump 32 based on the minute return amount change data, the controller 58 also becomes expensive.

As described above, it becomes expensive and it is difficult to commercialize it in terms of cost. Further, when a current is supplied to the electromagnetic pump, that is, the coil, the plunger moves forward against the elastic force of a spring or the like as the fuel supply pump 32, and when the current is stopped, the plunger moves backward by the elastic force of the spring to perform a pumping operation. If you use the one, because the fuel supplied by one pump action will be determined,
It is difficult to finely control the supplied fuel and it is difficult to stably maintain an appropriate amount of combustion continuously.

The present invention has been made to solve the above problems, and has as its object to always obtain an appropriate combustion amount of a combustion device.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a liquid fuel combustion apparatus according to the present invention is provided with an atomizing means for atomizing liquid fuel, and a cylindrical mixing device having the atomizing means facing a side wall. Chamber, a cylindrical transport passage penetrating the top plate of the mixing chamber, and provided in the mixing chamber, a flame port provided at an upper portion of the transport passage, and a bottom provided in the mixing chamber. In a combustion apparatus having a fuel return pipe for liquid fuel, a fuel return pump is provided in the middle of the fuel return pipe, and the other end is connected to a fuel supply pump for supplying fuel from the atomizing means to the atomizing means. It is connected to a fuel supply pipe which is a path leading to the fuel supply pipe.

In the above-mentioned fuel return pipe, a pressure adjusting chamber having an appropriate volume is provided between a path from the fuel return pump to a connection portion between the fuel return pipe and the fuel supply pipe.

Further, a through hole is provided in an upper portion or a side portion of the pressure adjusting chamber.

Further, the pressure adjusting chamber is configured such that the bottom portion is located at a position higher than the ejection port of the atomizing means.

[0018]

According to the liquid fuel combustion apparatus of the present invention, only the particles having a small particle diameter and a small particle diameter close to the vaporized gas among the fuel particles atomized by the atomizing means are selected in the mixing chamber by the above-mentioned structure, and Particles having a large particle size are forcibly condensed in the mixing chamber, and are supplied again from the bottom of the mixing chamber directly to the atomizing means by a fuel return pump via a fuel return pipe,
Since it is not returned to the constant oil level device, it is possible to always obtain an appropriate and stable combustion amount in response to fluctuations in the return amount at the start of the combustion device and increase in the return amount due to temperature drop. . In other words, the fuel returned by the fuel return pump is directly supplied again to the atomizing means without passing through the fuel supply pump, so that the fuel supply pump supplies the prescribed supply amount regardless of the amount of fuel returned. It should just be.

Since the pressure control chamber has an appropriate volume, that is, a fuel reservoir, even if the fuel returned by the fuel return pump temporarily increases and exceeds the atomizing capability of the atomizing means, the fuel is controlled. There is no problem with temporary pooling.

When the amount of fuel returned by the fuel return pump is small together with the fuel, air is also sent. However, since the air is discharged through the through hole of the pressure adjusting chamber, it does not affect the atomizing means.

That is, since a through hole is provided in the upper portion or the side portion of the pressure adjusting chamber, the fuel does not overflow but the air escapes. Of course, the pressure of the fuel by the fuel return pump is also adjusted by the air escaping from the through hole.

Further, since the bottom of the pressure adjusting chamber is located higher than the outlet of the atomizing means, the fuel from the fuel supply pump does not go to the atomizing means and does not go to the pressure adjusting chamber.

In this manner, an appropriate and stable combustion amount can be always obtained even when there is a transition from the start of the combustion apparatus to a stable state, a fluctuation in temperature, a fluctuation in fuel return amount due to a fluctuation in equipment, and the like. Will be.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes atomizing means using an ultrasonic spray nozzle or the like for atomizing and spraying liquid fuel by ultrasonic vibration, and is connected to a fuel supply pump 2 by a fuel supply pipe 3. The fuel supply pump 2 is connected to a fuel tank (not shown) via a constant oil level device 4. Reference numeral 5 denotes a combustion air passage provided around the atomizing means 1, and is connected to a blowing means (not shown) using a blowing fan or the like.

Reference numeral 6 denotes a cylindrical mixing chamber, and an opening 8 of the air passage 5 is provided in a part of the curved side wall 7 so as to face the inside of the mixing chamber 6. Spout 2
6 is also provided so as to face the mixing chamber 6. The air passage 5 is provided in the side wall 7 in a tangential direction or a direction close thereto. The lower part of the mixing chamber 6 has an inclined bottom 9
A return port 10 is provided at the lowermost end, and a fuel return pipe 17 is connected to the return port 10.

The upper portion of the mixing chamber 6 is covered with a top plate 11, and a cylindrical transfer passage 12 is provided substantially at the center of the top plate 11 so as to pass through the top plate 11. The lower end of the transport passage 12 extends below a position where the opening 8 of the air passage 5 in the mixing chamber 6 is exposed, and is provided with a gap 13 from the bottom 9. A mixing passage 14 configured to gradually expand upward and a porous flame port 15 provided in the middle of the mixing passage 14 are provided at an upper portion of the transport passage 12.

Reference numeral 16 denotes a fuel return pump provided in the middle of the fuel return pipe 17, which is connected via the fuel return pipe 17 to a pressure adjusting chamber 18 having an appropriate volume. A fuel supply pump 2 for supplying fuel from the atomizing means 1 to the atomizing means 1 from the pressure adjusting chamber 18 via a fuel return pipe 25.
Connecting part 24 with the fuel supply pipe 3 which is a path leading to
It is connected to the.

The bottom of the pressure adjusting chamber 18 is located at a position higher than the outlet 26 of the atomizing means 1.
A through hole 22 is provided in an upper portion or a side portion of the pressure adjustment chamber 18. 21 is an air flow, 19 is atomized fuel particles, 2
0 is a flame.

In the above configuration, a blowing means (not shown)
Is operated, the air flow 21 flows through the air passage 5 into the mixing chamber 6. Since the air flow 21 flows into the mixing chamber 6 from the tangential direction, the air flow 21 turns along the inner wall of the curved side wall 7 and descends along the inclined bottom 9 while rotating around the transport passage 12, Through the gap 13, the transport path 12
Rises to the flame outlet 15.

At this time, when the fuel supply pump 2 is operated, the fuel is sent to the atomizing means 1 through the fuel supply pipe 3,
The fuel particles 19 are sprayed into the mixing chamber 6 as atomized fuel particles 19.
The atomized fuel particles 19 are swirled along the curved side wall 7 and the inclined bottom 9 while being mixed with the air flow 21, and only the fuel particles having a small particle diameter are mixed with the air flow in the transport passage 12. And is ejected from the flame outlet 15. Then, ignition is performed by an igniter (not shown), and a flame 20 is formed on the flame opening portion 15, and the combustion is continued.

Large fuel particles that have adhered to or fall on the curved side wall 7 or the inclined bottom 9 wall pass through the fuel return pipe 17 from the return port 10 at the lowermost end of the bottom 9 of the mixing chamber 6. The fuel is returned to the pressure adjustment chamber 18 by the fuel return pump 16.

The fuel from the fuel supply pump 2 and the return fuel from the pressure adjusting chamber join at the connection portion 24 between the fuel return pipe 25 and the fuel supply pipe 3 and are supplied to the atomizing means 1 together. The atomizing means 1 atomizes the supplied liquid fuel by ultrasonic vibration and sprays it from the ejection port 26.

A through hole 22 is provided in the upper portion or a side portion of the pressure adjusting chamber. When the return amount of the fuel is small, the fuel is returned by the fuel return pump 16 together with the fuel. This is to release the pressure by the fuel return pump 16 such as by bleeding the air. In this way, the pressure by the fuel return pump 16 does not adversely affect the atomizing means 1.

Here, the bottom of the pressure regulating chamber 18 is
Because it is located higher than the outlet 26 of
The fuel from the fuel supply pump 2 goes to the pressure adjustment chamber 18 and does not overflow from the through hole 22 of the pressure adjustment chamber 18.

Since the fuel return pipe 25 from the bottom of the pressure control chamber 18 to the connection portion 24 with the fuel supply pipe 3 functions in the same manner as the fuel reservoir, the capacity of the pressure control chamber 18 is taken into consideration. Can be determined.

Therefore, depending on the volume of the fuel return pipe 25, the pressure adjusting chamber 18 is not always necessary. However, as described above, since it is necessary to release the air from the fuel return pump 16 and adjust the pressure, it is better to provide an air release hole through which a portion of the fuel return pipe 17 (25) allows only the air to escape without overflowing the fuel. Of course, any structure may be used as long as air is released from the fuel reservoir when atomizing the liquid fuel with the ultrasonic atomizer of the atomizing means 1.

At this time, the fuel returned by the fuel return pump 16 is directly supplied to the atomizing means 1 and the fuel supply pump 2
, The fuel supply pump 2 only needs to supply the specified supply amount regardless of the amount of fuel return.
Since the fuel supply pump 2 has an oil inlet 23 below the oil level of the constant oil level device 4, only the liquid fuel is supplied to the atomizing means 1 through the fuel supply pipe 3.

Accordingly, there is an effect that a proper and stable combustion amount can always be obtained even when the return amount of fuel fluctuates due to a transition from the start of the combustion apparatus to a stable state, a fluctuation in air temperature, a fluctuation in equipment, and the like. .

In the mixing chamber 6, the fuel particles having a small particle diameter are sorted, so that the fuel particles are sufficiently mixed with the air flow 21 so as to be sent to the flame opening 15, and the fuel particles are also separated. It is instantaneously vaporized and a blue flame can be obtained by premixed combustion.

In this system, a heating means such as a heater is provided at the bottom 9 of the mixing chamber 6 so that dew-condensed fuel is not evaporated and vaporized, so that tar and the like, which are vaporized residues, hardly accumulate.

[0042]

According to the combustion apparatus of the present invention as described above, the following effects can be obtained.

(1) A fuel return pump is provided in the middle of the fuel return pipe, and the returned fuel is directly supplied to the atomizing means again and is not returned to the constant oil level device. The fuel supply pump can always maintain a proper and stable combustion amount as long as the specified supply amount is supplied, regardless of the transient change up to the above, the fluctuation of the temperature, the fluctuation of the return amount due to the fluctuation of the equipment, and the like.

(2) In the fuel return pipe, a pressure regulating chamber having an appropriate volume is provided between the fuel return pump and the path from the fuel return pipe to the connection between the fuel return pipe and the fuel supply pipe. Even if the control chamber becomes a fuel reservoir and the fuel returned by the fuel return pump temporarily exceeds the atomizing capability of the atomizing means, the fuel can be temporarily pooled and no problem such as fuel overflow occurs.

(3) When the amount of fuel returned is small together with the fuel by the fuel return pump, air is also sent. However, this air escapes through the through hole in the upper part or the side part of the pressure regulating chamber, so that it affects the atomizing means. Has no effect. Of course, the pressure of the fuel by the fuel return pump is also adjusted by the air escaping from the through hole.

(4) Since the bottom of the pressure adjusting chamber is located higher than the ejection port of the atomizing means, the fuel from the fuel supply pump does not go to the atomizing means and does not go to the pressure adjusting chamber.

In this way, an appropriate and stable combustion amount can be always obtained even when there is a change in the fuel return amount due to a transition from the start of the combustion device to a stable time, a change in temperature, a change in equipment, and the like. Will be.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a combustion apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of a conventional combustion device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 atomization means 2 fuel supply pump 3 fuel supply pipe 4 constant oil level device 5 (combustion) air passage 6 mixing chamber 12 transport passage 15 flame outlet 16 fuel return pump 17 fuel return pipe 18 pressure regulation chamber 22 through hole 24 Connecting portion between fuel return pipe 25 and fuel supply pipe 3 26 outlet

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F23D 11/24-11/30 F23K 5/02-5/04

Claims (4)

(57) [Claims] An atomizing means for atomizing a liquid fuel, a cylindrical mixing chamber having the atomizing means facing a side wall, a top plate of the mixing chamber, and provided in the mixing chamber. In a combustion device having a cylindrical transfer passage, a flame port provided at the top of the transfer passage, and a fuel return pipe for liquid fuel provided at the bottom of the mixing chamber, the combustion device has Liquid fuel combustion, characterized in that a fuel return pump is provided and the other end is connected to a fuel supply pipe which is a path from the atomizing means to a fuel supply pump for supplying fuel to the atomizing means. apparatus. 2. The liquid fuel combustion apparatus according to claim 1, wherein a pressure adjustment chamber is provided in the fuel return pipe between a path from the fuel return pump to a connection portion between the fuel return pipe and the fuel supply pipe. . 3. The liquid fuel combustion apparatus according to claim 2, wherein the pressure adjustment chamber has a through hole provided in an upper portion or a side portion thereof. 4. The liquid fuel combustion apparatus according to claim 2, wherein a bottom of the pressure adjustment chamber is located at a position higher than a discharge port of the atomizing means.