JP2004150711A - Thermal apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize combustion in a burner by correcting fluctuation of a feed gas pressure by a thermal apparatus itself. <P>SOLUTION: It is characterized by that a pressure raising means 10 for fuel gas is provided in a fuel gas pipe 7 in the thermal apparatus 1 feeding the gas fuel to a burner 2. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thermal device that burns gas fuel with a burner. In particular, the present invention relates to a thermal device having a low supply gas pressure (about 2 kPa).
[0002]
[Prior art]
In the conventional thermal equipment, when the supply gas pressure is low, a misfire, a misfire, or the like occurs due to a change in the supply gas pressure, and the combustion is not stable. Therefore, a pressure booster for raising the pressure of the gaseous fuel, that is, a so-called gas booster is provided in the fuel gas supply pipe (for example, see Patent Document 1). As shown in Patent Document 1, a conventional gas booster is often used for a large-sized thermal device, and has a high boosting capacity, is large, and is expensive. For this reason, there has been no thermal equipment for individually correcting the fluctuation of the supply gas pressure by the thermal equipment itself.
[0003]
[Patent Document 1]
Japanese Patent No. 2530913
[Problems to be solved by the invention]
The problem to be solved by the present invention is to correct the fluctuation of the supply gas pressure by the thermal equipment itself and to stabilize the combustion in the burner.
[0005]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and the invention according to claim 1 includes a fuel gas pressure increasing means in a fuel gas pipe in a heat appliance for supplying gas fuel to a burner. Features.
[0006]
The invention according to claim 2 is characterized in that a fuel gas pipe in a thermal device for supplying gaseous fuel to a burner is provided with a pressure increasing means having a pressure increasing ability to compensate for a pressure drop of the fuel gas.
[0007]
A third aspect of the present invention is characterized in that the fuel gas pressurizing section of the pressurizing means has a structure in which the driving motor section of the pressurizing means is airtightly shut off, and includes a sirocco fan. .
[0008]
The invention according to a fourth aspect is characterized in that the pressurizing means is provided at a bent portion of the fuel gas pipe.
[0009]
The invention according to claim 5 is characterized in that a gas pressure detecting means is provided downstream of the pressure increasing means, and a control means for controlling the operation of the burner based on a detected pressure value of the gas pressure detecting means is provided. Features.
[0010]
The invention according to claim 6 is provided with a gas pressure detecting means downstream of the pressure increasing means, and a control means for controlling the operation of the pressure increasing means based on a detected pressure value of the gas pressure detecting means. It is characterized by.
[0011]
Furthermore, the invention according to claim 7 is a control means for starting the operation of the pressure increasing means a predetermined time before the ignition of the burner, and controlling the operation of the pressure increasing means to be stopped together with the stop of the combustion of the burner. It is characterized by having.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described. INDUSTRIAL APPLICABILITY The present invention can be suitably implemented in thermal equipment when the supply gas pressure is low (about 2 kPa). The heat equipment is, for example, a boiler provided with a low-pressure gas-fired burner, a reheater of an absorption refrigerator, or the like.
[0013]
First, a first embodiment will be described. The thermal equipment according to the first embodiment includes a low-pressure gas-fired burner, a blower that supplies combustion air to the burner, and a controller that controls the operation of the thermal equipment.
[0014]
The burner is connected to a fuel gas pipe, which is a pipe in the heating device. The burner mixes gaseous fuel with combustion air supplied from the blower to perform combustion.
[0015]
The fuel gas pipe is provided with a fuel gas pressure increasing means. That is, this thermal equipment has the boosting means therein. The pressure increasing means is a small pressure increasing means having a pressure increasing ability to compensate for a decrease in the pressure value of the supplied low-pressure gas fuel. Therefore, since the pressure raising means is small, it can be easily incorporated into the fuel gas pipe, and can be built in the relatively small heat equipment.
[0016]
Thereby, the fluctuation of the supply gas pressure is corrected by the thermal equipment itself, for example, when the supply gas pressure is reduced, or when the supply gas pressure is expected to decrease, the booster is operated by a command from the controller, Since the gas pressure can be increased, non-ignition or misfire of the burner due to a decrease in the gas pressure can be eliminated, and combustion in the burner can be stabilized.
[0017]
Here, it is preferable that the pressure increasing means is configured to set the pressure value of the fuel gas to 2 to 2.5 kPa. That is, when the gas pressure value of the city gas or the like supplied at a low pressure at about 2 kPa fluctuates (for example, decreases to 1 kPa), the pressure increasing means sets the pressure value of the fuel gas to 2 to 2.5 kPa. To work. As described above, since the pressure raising means has a pressure raising ability of about 0.5 to 1.5 kPa, it is smaller than a conventional gas booster.
[0018]
In a preferred embodiment of the booster, the fuel gas booster of the booster has a structure that is hermetically isolated from the drive motor of the booster and includes a sirocco fan. And, since it is airtightly shut off from the drive motor, gas fuel does not ignite. Further, since the pressure is increased by the sirocco fan, the pressure is not excessively increased due to the characteristics of the sirocco fan, so that the pressure can be increased safely.
[0019]
As described above, according to the first embodiment, by incorporating the pressure increasing means, fluctuations in the supply gas pressure can be corrected by the thermal equipment itself, and combustion in the burner can be stabilized.
[0020]
Next, a second embodiment will be described. In the second embodiment, a gas pressure detecting means is provided in the thermal equipment in the first embodiment, and the operation of the pressure increasing means is confirmed by the gas pressure detecting means, so that the burner is more stably provided. It burns.
[0021]
The gas pressure detecting means is provided in the fuel gas pipe, and its location is on the downstream side of the pressure increasing means. The controller controls the following three patterns.
[0022]
First, as a first pattern, the controller detects the gas pressure value on the downstream side of the pressure increasing means by the gas pressure detecting means, and controls the operation of the burner based on the detected pressure value. Specifically, the controller stops the operation of the burner when the detected pressure value becomes lower than a predetermined pressure value. Thus, the burner can be safely stopped without misfire.
[0023]
Next, as a second pattern, the controller controls the operation of the booster based on the detected pressure value on the downstream side of the booster. More specifically, when the detected pressure value becomes higher than a predetermined pressure value, the controller stops the operation of the booster. Thereby, abnormal combustion of the burner can be prevented.
[0024]
Further, as a third pattern, when it is assumed that the supply gas pressure is reduced, the controller activates the pressure increasing means in advance in preparation for the decrease, for example, the pressure increase from a predetermined time before ignition of the burner. The operation of the means is started, and control is performed so as to stop the operation of the pressure increasing means together with the stop of combustion of the burner. That is, when the burner is ignited, if the pressure value of the gas fuel is surely maintained at a predetermined pressure value (for example, 2 to 2.5 kPa) and if the combustion of the burner is stopped, the burner is quickly stopped. Is controlled so that the boost operation is also stopped. Thus, the booster can be operated only when the burner is operating and boosting is required.
[0025]
As described above, according to the second embodiment, the gas pressure detecting means allows the thermal equipment to operate safely, and the controller sets the pressure increasing means only when pressure increase is required. Can be operated.
[0026]
Here, each of the three patterns can be performed independently, but it is also preferable to appropriately perform all or a combination of these.
[0027]
Next, a third embodiment will be described. The third embodiment is a modification of the first embodiment. That is, the pressurizing means is provided at a bent portion of the fuel gas pipe. More specifically, the pressurizing means is disposed at a bent portion of the fuel gas pipe, at a portion where a so-called elbow joint or the like is arranged, instead of the elbow joint or the like. That is, the pressure increasing means is configured so that the suction port and the discharge port have an angle of about 90 degrees, and can perform the same operation as changing the direction of the elbow joint or the like by 90 degrees.
[0028]
As described above, according to the third embodiment, the step-up means can be more compactly built in the heat appliance.
[0029]
【Example】
Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory perspective view showing a schematic configuration of a thermal device according to the present invention. First, a first embodiment will be described. In the first embodiment, a gas-fired boiler will be described as an example of the heat equipment. In FIG. 1, a boiler 1 includes a gas-fired burner 2 having a low supply gas pressure (about 2 kPa), a blower 3 for supplying combustion air to the burner 2, and a controller 4 for controlling the operation of the boiler 1. Are provided in the frame 5.
[0030]
The boiler 1 is a steam boiler that heats water stored inside by burning gas fuel with the burner 2 to generate steam.
[0031]
The burner 2 is provided on a front surface of the boiler 1 and is configured to form a combustion flame in a lateral direction. The burner 2 is connected to the blower 3 via a blow duct 6 and to a fuel gas pipe 7 in the frame 5 for supplying gaseous fuel. Then, the gas fuel and the combustion air supplied from the blower 3 are mixed to perform combustion.
[0032]
A low-pressure (about 2 kPa) gas is supplied to the fuel gas pipe 7 and passes through the boiler 1 from the lower rear surface in the boiler 1 through the right side surface (the right side surface in FIG. 1). 1 and is connected to the upper right side of the burner 2. The fuel gas pipe 7 is provided with a strainer 9 for removing dust in order from a gas fuel inlet 8, a fuel gas booster 10, a gas pressure detector 11, and a fuel control valve 12. I have. In this case, although not shown, it is also preferable to arrange a plurality of the fuel control valves 12 in series or to arrange them in parallel to switch between low combustion and high combustion, or to add a pressure control valve.
[0033]
The pressure increasing means 10 is a small pressure increasing means having a pressure increasing ability to compensate for a decrease in the pressure value of the supplied low-pressure gas fuel, and is configured so that the pressure value of the fuel gas is about 2 to 2.5 kPa. I do. That is, when the gas pressure value of the city gas or the like supplied at a low pressure at about 2 kPa fluctuates (for example, decreases to 1 kPa), the pressure increasing means 10 sets the pressure value of the fuel gas to 2 to 2.5 kPa. As described above, the boosting capacity is set to about 0.5 to 1.5 kPa.
[0034]
Here, the configuration of the downsized booster 10 will be described in detail with reference to FIG. FIG. 2 is a schematic explanatory view of a cross-sectional shape of the booster 10. In FIG. 2, the pressure increasing means 10 includes a fuel gas pressure increasing section 13 for increasing the pressure of gas and a driving motor section 14.
[0035]
The fuel gas pressurizing section 13 includes a small sirocco fan 15 having an outer diameter of about 100 to 150 mm, for example, and a pump casing 17 defining a pump chamber 16. The sirocco fan 15 is provided in the pump chamber 16. The pump casing 17 has a gas inlet 19 having a first flange 18 and a discharge port 21 having a second flange 20. Here, the pump chamber 16 is defined by the pump casing 17 and a partition wall 22 of the drive motor unit 14 on the opposite side (left side in FIG. 2) of the pump casing 17.
[0036]
The driving motor unit 14 includes the partition wall 22, a coil 24 disposed in a coil chamber 23, a motor cover 25 covering the coil 24 and defining the coil chamber 23, and a rotor inside the coil 24. It is constituted by a rotor chamber wall 27 defining a chamber 26 and a rotor 28 disposed in the rotor chamber 26. The rotor chamber 26 is defined by the rotor chamber wall 27 and the partition wall 22 hermetically joined thereto by welding or the like. By this airtight joining, the gas in the rotor chamber 26 does not leak to the coil chamber 23.
[0037]
The rotor 28 is supported by a first bearing 29 provided inside the rotor chamber wall 27 and a second bearing 30 provided substantially at the center of the partition 22, and penetrates through the rotor 28 and with the rotor 28. A rotating shaft 31 is provided.
[0038]
The pressure raising means 10 causes the shaft 31 to penetrate from the partition wall 22 to the pump chamber 16 side, and the sirocco fan 15 attached to the penetrated shaft 31 and the shaft 31 rotate integrally. It is configured to
[0039]
The blower 3 is provided above the boiler 1, and is configured to supply combustion air to the burner 2 via the blow duct 6.
[0040]
Further, the controller 4 communicates with the ignition means (not shown) of the burner 2, the blower 3, the pressure increasing means 10, the gas pressure detecting means 11, and the fuel control valve 12 via respective lines (not shown). It is connected.
[0041]
Now, the operation of the boiler 1 having such a configuration will be described. First, the operation of the booster 10 on the burner 2 will be described. When it is necessary to increase the pressure of the gaseous fuel, when the controller 4 supplies electric power to the coil 24, the rotor 28 rotates and the sirocco fan 15 rotates via the shaft 31. To increase the pressure of the gas fuel.
[0042]
Accordingly, the sirocco fan 15 rotates in the pump chamber 16 which is airtightly cut off from the energized drive motor unit 14, so that gas fuel does not leak and ignite. Further, since the boosting means 10 is of a sirocco fan type, the pressure is not excessively increased, so that the pressure is increased safely.
[0043]
Then, even if the gas pressure drops, the boiler 1 burns the gas fuel brought into a state of 2 to 2.5 kPa by the pressurizing means 10 with the burner 2 to heat the water in the boiler 1. To generate steam.
[0044]
The booster 10 is characterized by a sirocco fan type having a small pressure loss when gaseous fuel passes therethrough, so that it is not necessary to operate the booster 10 (for example, a gas pressure of 2 to 2.5 kPa). Even when the fuel is supplied and the pressure increasing means 10 is not operated), the gas fuel passes through the pressure increasing means 10, so that the supply of the gas fuel to the burner 2 does not hinder.
[0045]
As described above, according to the first embodiment, by incorporating the pressure increasing means 10 in the boiler 1, the fluctuation of the supply gas pressure is corrected by the boiler 1 itself, and the combustion in the burner 2 is stabilized. Can be done.
[0046]
Next, a second embodiment will be described. In the second embodiment, in addition to the configuration of the first embodiment, the controller 4 confirms the operation of the pressure increasing means 10 based on the detected pressure value of the gas pressure detecting means 11, and 2 controls the combustion or controls the boosting means 10.
[0047]
A description will be given based on FIG. First, the controller 4 detects the gas pressure value on the downstream side of the pressure increasing means 10 by the gas pressure detecting means 11, and controls the operation of the burner 2 based on the detected pressure value. More specifically, the controller 4 stops the operation of the burner 2 when the detected pressure value becomes lower than, for example, 1 kPa. As a result, the burner 2 is safely stopped without misfire.
[0048]
Further, the controller 4 controls the operation, for example, the rotation speed of the booster 10 based on the detected pressure value on the downstream side of the booster 10. The controller 4 controls the rotation speed so that the detected pressure value becomes 2 to 2.5 kPa. For example, when the detected pressure value becomes higher than 2.5 kPa, the operation of the booster 10 is stopped. Thereby, abnormal combustion of the burner 2 is prevented.
[0049]
Further, the controller 4 starts the operation of the pressure increasing means 10 before the pre-purge time before the ignition of the burner 2, and continues the operation of the pressure increasing means 10 during the combustion of the burner 2. Control is performed so that the operation of the booster 10 is stopped together with the stop of combustion in step 2. That is, while the burner 2 is ignited from the time of ignition, the pressure value of the gaseous fuel is reliably maintained at 2 to 2.5 kPa, and if the combustion of the burner 2 is stopped, the pressure is immediately increased. The operation is controlled to stop.
[0050]
As described above, according to the second embodiment, the gas pressure detecting means 11 safely operates the boiler 1 and stabilizes the combustion of the burner 2.
[0051]
Here, the position at which the pressure increasing means 10 is provided will be described. The pressure increasing means 10 is provided at a bent portion 32 of the fuel gas pipe 7 as shown in FIG. That is, instead of the elbow joint or the like, the boosting means 10 is arranged at a position where the bent portion 32, a so-called elbow joint (not shown), or the like is arranged. The pressure increasing means 10 is configured so that the suction port 19 and the discharge port 21 have an angle of substantially 90 degrees, and can perform the same function as changing the direction of the elbow joint or the like by 90 degrees. Thereby, the booster 10 can be more compactly built in the boiler 1.
[0052]
Here, the fuel gas pipe 7 has been described as a pipe from the lower rear surface of the boiler 1, but the pressure increasing means 10 is also provided at the bent portion 32 of the pipe when changing the direction by 90 degrees from another direction. Arrangement is also suitable.
[0053]
【The invention's effect】
As described above, according to the present invention, the fluctuation in the supply gas pressure can be corrected by the thermal equipment itself, and the combustion in the burner can be stabilized.
[Brief description of the drawings]
FIG. 1 is a perspective explanatory view showing a schematic configuration of a thermal device according to the present invention.
FIG. 2 is a schematic explanatory view of a cross-sectional shape of a booster.
[Explanation of symbols]
1 Boiler (thermal equipment)
2 Burner 4 Controller (control means)
7 Fuel Gas Pipe 10 Booster 11 Gas Pressure Detector 13 Fuel Gas Booster 14 Driving Motor 15 Sirocco Fan 32 Bent

Claims (7)

A heating apparatus characterized in that a fuel gas pipe (7) in a heating apparatus (1) for supplying gaseous fuel to a burner (2) is provided with a fuel gas booster (10). A heating apparatus characterized in that a fuel gas pipe (7) in a heating apparatus (1) for supplying gaseous fuel to a burner (2) is provided with a boosting means (10) having a boosting capacity enough to compensate for a decrease in pressure of fuel gas. The fuel gas booster (13) of the booster (10) has a structure in which the fuel gas booster (13) is airtightly cut off from the drive motor (14) of the booster (10), and includes a sirocco fan (15). The thermal device according to claim 2. The thermal equipment according to claim 1 or 2, wherein the pressure increasing means (10) is provided at a bent portion (32) of the fuel gas pipe (7). A gas pressure detecting means (11) is provided downstream of the pressure increasing means (10), and a control means (4) for controlling the operation of the burner (2) based on a detected pressure value of the gas pressure detecting means (11) is provided. The thermal device according to claim 1 or 2. Gas pressure detecting means 11 is provided downstream of the pressure increasing means 10, and control means 4 for controlling the operation of the pressure increasing means 10 based on the detected pressure value of the gas pressure detecting means 11 is provided. The thermal device according to claim 1 or 2. Control means 4 is provided which starts the operation of the pressure increasing means 10 a predetermined time before the ignition of the burner 2 and controls the operation of the pressure increasing means 10 to stop at the same time as the combustion of the burner 2 is stopped. The thermal device according to claim 1 or 2, wherein

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