JPH0596714U - Burning variable oil burner and water heater or bath kettle equipped with the burner - Google Patents

Abstract

(57) [Summary] [Purpose] The combustion air is made uniform and the flow direction is optimized, and there is no soot adhesion to the burner, combustion chamber, heat exchanger, etc. over a wide range of turndown ratio, and it is stable. To provide a variable burner oil burner capable of excellent combustion. A small-diameter inner cylinder 3 is arranged inside an outer cylinder 4 via an air passage 9 that is ventilated from a rear air chamber 8 by a blower 16, and the inner cylinder 3 is communicated with the air chamber 8 at the rear part. In addition to opening the primary air introduction port 10, a variable flow atomizer 2 for liquid fuel is arranged near the rear part of the inner cylinder 3 with the spray port 1 on the front side, and on the front side of the spray port 1. The swirler 12 having a plurality of swirl vanes 13 is provided, and the inner cylinder 3 on the front side of the swirler 12 is provided with a plurality of rows of secondary air inlets 15 each having a plurality of openings in one row. In the combustion amount variable petroleum burner, an air swirl chamber 5 is arranged outside the air chamber 8, and an air introduction port 6 having a plurality of openings is provided between the air chamber 8 and the air swirl chamber 5. And the blower 16 is arranged so that the air is swirled in the air swirl chamber 5 from the tangential direction. Burnable oil burner.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a variable burner oil burner and a household proportional control type oil water heater or hot water bath equipped with the burner.

[0002]

[Prior Art]

 Household petroleum water heaters, bath kettles with hot water, etc. require precise control of the hot water discharge temperature. Therefore, burners used in these appliances have been burned as shown in Figs. 7 and 8. Variable volume oil burners are known. FIG. 7 is a cross-sectional view of an essential part showing the structure of a conventional variable burner oil burner, and FIG. 8 is a cross-sectional view taken along line AA of FIG. In this type of burner, an inner cylinder 3 having a diameter smaller than that of the outer cylinder 4 is arranged inside the outer cylinder 4 via an air passage 9 that is ventilated from an air chamber 8 by a blower 16, and the inner cylinder 3 is provided at the rear part thereof. A primary air inlet 10 communicating with the air chamber 8 is opened, and a return pressure atomizing nozzle 2 which is a variable flow atomizer for liquid fuel is provided near the rear part of the inner cylinder 3 with the atomizing port 1 on the front side. is set up. Further, a swirler 12 having a plurality of swirl vanes 13 is installed on the front side of the spray port 1 so that the primary combustion is performed while swirling the introduced primary air. Further, on the front side of the swirler 12 of the inner cylinder 3, a plurality of rows of secondary air inlets 15 each having a plurality of openings in one row are provided, which promotes secondary combustion. Is configured. In the figure, 17 is a fuel leveler, 18 is a pump, 19 is a return flow rate adjusting valve, and 28 is an ignition electrode.

[0003]

[Problems to be solved by the device]

 In the above-mentioned household proportional control type oil water heater, it is necessary to finely control the temperature of tap water. Therefore, a burner that can satisfactorily burn in a wide range with a turndown ratio of about 1 to 1/5 is required. However, in the above-described conventional burner, the flow velocity distribution at the air discharge portion of the blower 16 affects the flow velocity distribution of the combustion air introduced from the primary air inlet 10 or the secondary air inlet 15 on the downstream side. Figure 9 shows the flow velocity distribution of secondary air from a conventional variable burner oil burner. This is the result of measurement with a burner having three rows of secondary air inlets 15 each having 12 openings in one row. In the secondary air inlet port position shown on the horizontal axis, 1 corresponds to the position directly above in FIG. 7, which is in the clockwise direction when viewed from the downstream side of the burner. The right half has a high velocity of secondary air as seen from the downstream of the burner, and the left half has a slow velocity.

Similarly to this, the flow velocity distribution also occurs in the primary air introduced from the primary air inlet 10 and swirled by the swirler 12. Therefore, a current plate (not shown) is installed in the air chamber 8 or the air passage 9 to suppress the flow velocity distribution of the combustion air. However, in order to make the flow velocity distribution of the combustion air uniform, an increase in pressure loss due to the straightening vanes is unavoidable, and it is necessary to enlarge the blower 16. Further, since the flow velocity distribution at the air discharge part of the blower 16 where the air amount changes also changes, it is difficult to make the flow velocity distribution of the combustion air uniform in a wide range of the air amount that changes according to the turndown ratio. Is. When non-uniformity occurs in the swirling flow of primary air, the oxygen concentration in the swirling flame becomes extremely low locally, and the soot concentration in the flame becomes high. On the small turndown ratio side where the amount of combustion is small, the kerosene particles sprayed from the spray port 1 do not undergo a sufficient evaporation process and combustion starts near the central opening 14 of the swirler 12 to form a swirling flame. It Therefore, there is a problem that soot in the flame becomes soot and adheres to the swirl vanes 13 of the swirler 12 and the inner wall of the inner cylinder 3. Furthermore, since the flame length is short and the high temperature range is narrow, it is not possible to sufficiently reduce the high-concentration soot and smoke in the combustion gas, and the CO concentration and smoke scale in the exhaust gas become high, so good combustion performance cannot be secured. was there.

On the other hand, on the large turndown ratio side where there is a large amount of combustion, the flame shape becomes non-uniform due to the non-uniformity of the swirling flow of the primary air and the secondary air, so that soot adheres to the inner wall of the combustion chamber. was there. Furthermore, because it becomes partly longer and contacts the heat exchanger, soot adheres to the fins of the heat exchanger, CO concentration in the exhaust gas and smoke scale become high, and good combustion performance cannot be ensured. There was a problem. Further, since the blower 16 is installed at the rear part in the axial direction of the burner, the return type pressure spray nozzle 2 and the ignition electrode 28 are installed so as to penetrate the inner cylinder 3 and the outer cylinder 4, so that at the time of assembly or replacement of parts. There was a problem in workability at the time. Therefore, when the burner having the above conventional structure is applied to a proportional control type oil water heater, stable combustion cannot be stably performed in a wide range of the turndown ratio, and the burner, the combustion chamber, the heat exchanger, etc. There is a possibility of clogging due to the adhesion of soot.

The present invention eliminates the drawbacks of the above-described conventional burner, has a wide range of turndown ratios, has no soot adhesion to the burner, the combustion chamber, the heat exchanger, etc., and stably and satisfactorily burns. It is an object of the present invention to provide a combustion amount variable petroleum burner which has excellent workability at the time of parts replacement and small pressure loss, and a water heater or a bathtub with hot water supply equipped with the burner.

[0007]

[Means for Solving the Problems]

 According to the present invention, an inner cylinder having a small diameter is provided inside an outer cylinder through an air passage that is ventilated from a rear air chamber by a blower, and a primary air inlet opening communicating with the air chamber is provided at the rear of the inner cylinder. Along with opening, a variable flow atomizer for liquid fuel is placed near the rear of the inner cylinder with the spray port on the front side, and there are multiple swirl vanes on the front side of the spray port. In a combustion amount variable oil burner in which a swirler is provided and a plurality of rows of secondary air inlets in which a plurality of openings are opened in one row are provided in the inner cylinder on the front side of the swirler, An air swirl chamber is arranged outside the chamber, and an air inlet consisting of a plurality of openings is provided between the air chamber and the air swirl chamber to communicate with each other. Ventilation is tangential to the air swirl chamber. Combustion amount variable oil burner with a blower installed as described above, and the space between the air chamber and the air swirl chamber. The inlet, to the water heater or bath heater with hot water having a combustion amount varying oil burner and said burner is provided with air guide plate obtained by molding cut and raised on the air chamber side in parallel with the burner axis openings.

[0008]

[Action]

 According to the variable combustion amount oil burner of claim 1 of the present invention, since the air is introduced into the air chamber while swirling in the air swirling chamber according to the above-mentioned configuration, the flow velocity at the air discharge portion of the blower. The influence of the distribution is mitigated by swirling, and the flow velocity distribution of the air introduced into the air chamber is made uniform. As a result, both primary air and secondary air are introduced uniformly, and a uniform swirl flame is formed, so the oxygen concentration in the swirl flame does not become extremely low locally, and the soot concentration in the flame decreases. To do. Further, the invention of claim 2 is a further improvement of the variable combustion amount oil burner of claim 1, wherein the air introduced into the air chamber from the air swirling chamber is suppressed by the air guide plate, and the swirling component is suppressed, so that it is parallel to the burner axis. It becomes a flow. As a result, the primary air becomes a flow with no swirl component and is introduced into the inner cylinder of the primary air inlet port, part of which is swirled by the swirl vanes of the swirler, and the rest is free of swirl component from the central opening. The flow becomes parallel to the burner axis and jets out. Therefore, combustion does not start near the central opening of the swirler, and another swirl flame is not formed inside the swirl flame by the swirl vanes, and the sprayed kerosene particles undergo a sufficient evaporation process. After that, sufficient oxygen necessary for combustion is supplied and burned, and the secondary air also penetrates sufficiently into the flame, so the CO concentration and soot concentration in the flame decrease. Therefore, in a wide range of turndown ratio, there is no soot attachment to the burner, combustion chamber, heat exchanger, etc., and stable and good combustion performance is exhibited. Further, the water heater or the bath kettle with hot water supply exhibits the same combustion performance by including the variable combustion amount oil burner.

[0009]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Embodiment 1 FIG. 1 is a view showing a main part of a combustion amount variable oil burner according to an embodiment of the present invention, and FIG. 2 is a view showing a sectional view taken along the line AA of FIG. In the figure, parts having the same configurations as those of the conventional burnable variable oil burner of FIGS. 7 and 8 are designated by the same reference numerals. In this combustion amount variable oil burner, an inner cylinder 3 having a small diameter is arranged inside an outer cylinder 4 through an air passage 9 which is ventilated from a rear air chamber 8 by a blower 16. A primary air inlet 10 communicating with the air chamber 8 is provided at the rear of the inner cylinder 3. Further, a return type pressure spray nozzle 2 which is a variable flow atomizer for liquid fuel is installed near the rear part of the inner cylinder 3 with the spray port 1 on the front side, and the front side of the spray port 1 is at the center. A central opening 14 and a swirler 12 having a plurality of swirl vanes 13 around the central opening 14 are installed therein. The inner cylinder 3 on the front side of the swirler 12 is provided with a plurality of rows of secondary air inlets 15 each having a plurality of openings in one row in the circumferential direction. Here, an air swirl chamber 5 communicating with the air chamber 8 is arranged outside the air chamber 8, and a blower 16 is arranged so that the air swirling chamber 5 is ventilated in a tangential direction.

Next, the operation of the above configuration will be described. The kerosene that has flowed into the leveler 17 from the kerosene tank due to the head difference is pressurized by the pump 18, supplied to the return type pressure spray nozzle 2, and sprayed from the spray port 1. A part of the kerosene passes through the return flow rate adjusting valve 19 and returns to the leveler 17. Here, if the valve opening of the return flow rate adjusting valve 19 is increased, the return kerosene flow rate increases and the combustion amount decreases. Conversely, if the valve opening is made smaller, the amount of combustion becomes larger and the amount of combustion can be changed. The combustion air sent from the blower 16 enters the air swirl chamber 5 tangentially to the air swirl chamber 5 and swirls in the air swirl chamber 5. The air swirl chamber 5 has a smaller passage area downstream in the swirl direction, and combustion air is uniformly introduced into the air chamber 8 through the plurality of air inlets 6. A part of the combustion air introduced into the air chamber 8 enters the inner cylinder 3 through the primary air inlet 10 and is swirled by the swirler 12. The remaining combustion air passes through the air passage 9 and is ejected from the secondary air introduction port 15 into the inner cylinder 3.

FIG. 3 shows a flow velocity distribution of secondary air by the variable combustion amount oil burner of the present embodiment. This is the result of measurement by a burner provided with three rows of secondary air inlets 15 each having 12 openings in one row. In the secondary air inlet position on the horizontal axis, 1 corresponds to the position directly above in FIG. 1, and is in the clockwise direction when viewed from the downstream side of the burner. The flow velocity distribution is smaller than that in FIG. 9, and the secondary air is uniformly ejected from the secondary air inlet 15. Similarly, the primary air introduced from the primary air inlet 10 and swirled by the swirler 12 is also uniform. Therefore, a uniform swirl flame is formed, the oxygen concentration in the swirl flame does not become extremely low locally, and the combustion is promoted by the secondary air supplied from the secondary air introduction port 15 of the inner cylinder 3. .. Therefore, in a wide range of turndown ratio, soot does not adhere to the burner, combustion chamber, heat exchanger, etc., and stable and good combustion characteristics are exhibited.

Embodiment 3 FIG. 4 is a view showing a main portion of a combustion amount variable oil burner according to another embodiment of the present invention, and FIG. 5 is a sectional view taken along line AA of FIG. As shown in FIGS. 4 and 5, the configuration is the same as that of the first embodiment except that an air guide plate 7 formed by cutting and raising is provided on the air chamber 8 side of the air introduction port 6 in parallel with the burner axis. Next, with respect to the operation of the combustion amount variable petroleum burner having the above-described configuration, differences from the first embodiment will be described. The combustion air introduced into the air chamber 8 is suppressed in its swirling portion by the air guide plate 7 and becomes a flow parallel to the burner axis. Combustion air is divided into primary air and secondary air, the primary air is introduced into the inner cylinder 3 through the primary air inlet 10, part of which is swirled by the swirl vanes 13 of the swirler 12, and the rest is the central opening. From the part 14, the flow becomes parallel to the burner axis and jets out respectively. On the other hand, the secondary air is introduced into the inner cylinder 3 from the secondary air introduction port 15 through the air passage 9, and is ejected as a flow toward the central axis of the burner. Therefore, combustion does not start near the central opening 14 of the swirler 12, another swirl flame is not formed inside the swirl flame by the swirl vanes 13, and the sprayed kerosene particles undergo a sufficient evaporation process. After that, sufficient oxygen necessary for combustion is supplied and burned, and the secondary air sufficiently penetrates into the flame, so that the combustion is promoted and the C 2 O 3 concentration and soot concentration in the flame decrease. Therefore, in a wide range of turndown ratio, soot does not adhere to the burner, combustion chamber, heat exchanger, etc., and stable and good combustion performance is achieved.

Embodiment 4 FIG. 6 is a diagram showing a configuration of a water heater using a combustion amount variable oil burner according to an embodiment of the present invention. In this water heater, a variable combustion amount oil burner 20 is desired in the combustion chamber 21, a heat exchanger 22 is provided above the combustion chamber 21, and a silencer 23 is provided above the heat exchanger 22. It is a thing. When a water tap (not shown) provided in a washroom, a kitchen, etc. is opened, the water flow switch 24 is actuated, and the kerosene that flows into the leveler 17 from the kerosene tank 25 due to the head difference is pressurized by the pump 18. It is sent to the variable burner oil burner 20 and burns while being mixed with the combustion air ventilated by the blower 16. The combustion gas heats water in the heat exchanger 22 above the combustion chamber 21, and the exhaust gas is silenced and discharged by the silencer 23. The temperature detector 26 provided at the outlet of the heat exchanger 22 detects the hot water temperature, and the valve opening of the return flow rate adjusting valve 19 and the amount of combustion air ventilated from the blower 16 to reach the set hot water temperature. Can be controlled by the control circuit 27 to adjust the combustion amount. Also, in the case of a bath kettle with hot water supply, a burner for the bath, a heat exchanger, and the like are added to the water heater.

[0014]

[Effect of the device]

 According to the present invention, an air swirl chamber communicating with the air chamber is arranged outside the air chamber, and the blower is arranged so as to ventilate the air swirl chamber in a tangential direction. Since there is no need to install such as, and the pressure loss is small, combustion air can be supplied uniformly even with a small blower, and a uniform swirling flame and a uniform flame are formed. In addition, an air guide plate formed by cutting and forming an opening on the air chamber side was provided parallel to the burner axis at the air inlet between the air chamber and the air swirl chamber, so The swirling part of the jet of air can be suppressed, and the jet of air from the secondary air inlet can be made to flow toward the burner central axis. As a result, a good swirling flame and a uniform, untwisted flame are formed. Therefore, in a wide range of turndown ratio, there is no soot attachment to the burner, the combustion chamber, the heat exchanger, etc., and there is an advantage that good and stable combustion performance can be exhibited. Further, since it is not necessary to install the nozzle and the ignition electrode through the inner cylinder and the outer cylinder, it is possible to provide a burner excellent in workability during assembly and replacement of parts.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an essential part showing the configuration of a combustion amount variable oil burner according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a graph showing a flow velocity distribution of secondary air by a combustion amount variable oil burner according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view of an essential part showing the structure of a combustion amount variable oil burner according to another embodiment of the present invention.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a cross-sectional view of essential parts showing the configuration of a water heater including a variable combustion amount oil burner according to an embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts showing a configuration of a conventional burner amount variable oil burner.

8 is a cross-sectional view taken along the line AA of FIG.

FIG. 9 is a graph showing a flow velocity distribution of secondary air by a conventional combustion amount variable oil burner.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Spray port, 2 ... Return type pressure spray nozzle, 3 ... Inner cylinder, 4
... Outer cylinder, 5 ... Air swirl chamber, 6 ... Air inlet, 7 ... Air guide plate, 8 ... Air chamber, 9 ... Air passage, 10 ... Primary air inlet, 12 ... Swirler, 13 ... Swirling blade, 14 ... central opening, 15 ... secondary air inlet, 16 ... blower, 17 ... leveler, 18 ... pump, 19 ... return flow rate adjusting valve, 20 ... combustion amount variable oil burner, 21 ... combustion chamber, 22 ... heat exchanger Two
3 ... Silencer, 24 ... Water flow switch, 25 ... Kerosene tank, 26 ... Temperature detector, 27 ... Control circuit, 28 ... Ignition electrode, 29 ... Water heater main body

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Creator Koji Tajima 1500 Ogawa, Shimodate, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Shimodate Research Center

Claims (4)

[Scope of utility model registration request] 1. An inner cylinder having a small diameter is disposed inside the outer cylinder via an air passage ventilated from a rear air chamber by a blower,
A primary air introduction port communicating with the air chamber is opened at the rear of the inner cylinder, and a variable flow atomizer for liquid fuel is arranged near the rear of the inner cylinder with the spray port on the front side, and the spray is used. A swirler having a plurality of swirl vanes is provided on the front side of the mouth, and the inner cylinder on the front side of the swirler has a plurality of rows of secondary air inlets each having a plurality of openings in one row. In the provided combustion amount variable petroleum burner, an air swirl chamber is provided outside the air chamber, and an air inlet consisting of a plurality of openings is provided between the air chamber and the air swirl chamber so that they communicate with each other. A combustion amount variable petroleum burner in which a blower is arranged so as to ventilate the air swirl chamber from a tangential direction. 2. An air guide plate formed by cutting and raising an opening to the air chamber side at an air introduction port between the air chamber and the air swirl chamber in the variable combustion amount oil burner according to claim 1, and being parallel to the burner shaft. A variable burner oil burner installed in the. 3. The variable-combustion-quantity petroleum burner according to claim 1, wherein the variable-flow atomizer is a return-type pressure spray nozzle that is returned to the leveler via a return-flow control valve. 4. A water heater or a bath kettle with hot water supply, comprising the petroleum burner with variable combustion amount according to claim 1, 2, or 3.